Soal Dan Jawaban Heizer

SOAL DAN JAWABAN: MANAJEMEN OPERASIONAL Dari buku Manajemen Operasional oleh Render, Barry and Jay Heizer, Principles Of Operations Management, Prentice Hall, 9th edition.

Chapter 1, Operations and Productivity Problem 1: Mance Fraily, the Production Manager at Ralts Mills, can currently expect his operation to produce 1000 square yards of fabric for each ton of raw cotton. Each ton of raw cotton requires 5 labor hours to process. He believes that he can buy a better quality raw cotton, which will enable him to produce 1200 square yards per ton of raw cotton with the same labor hours. What will be the impact on productivity (measured in square yards per labor-hour) if he purchases the higher quality raw cotton?

Problem 2: C. A. Ratchet, the local auto mechanic, finds that it usually takes him 2 hours to diagnose and fix a typical problem. What is his daily productivity (assume an 8 hour day)? Mr. Ratchet believes he can purchase a small computer trouble-shooting device, which will allow him to find and fix a problem in the incredible (at least to his customers!) time of 1 hour. He will, however, have to spend an extra hour each morning adjusting the computerized diagnostic device. What will be the impact on his productivity if he purchases the device?

Problem 3: Joanna French is currently working a total of 12 hours per day to produce 240 dolls. She thinks that by changing the paint used for the facial features and fingernails that she can increase her rate to 360 dolls per day. Total material cost for each doll is approximately $3.50; she has to invest $20 in the necessary supplies (expendables) per day; energy costs are assumed to be only $4.00 per day; and she thinks she should be making $10 per hour for her

time. Viewing this from a total (multifactor) productivity perspective, what is her productivity at present and with the new paint?

Problem 4: How would total (multifactor) productivity change if using the new paint raised Ms. French’s material costs by $0.50 per doll?

Problem 5: If she uses the new paint, by what amount could Ms. French’s material costs increase without reducing total (multifactor) productivity?

ANSWERS:

Problem 1:

Current labor productivity =

New labor productivity =

1000 sq yds = 200 sq yds per hour 1 ton*5 hours

1200 sq yds = 240 sq yds per hour 1 ton * 5 hours

Productivity improves 20% = ( 240 - 200 ) / 200 = .2

Problem 2:

Current productivity =

8 hours per day = 4 problems per day 2 hours per problem

Productivity with computer =

7 hours per day = 7 problems per day 1 hour per problem

7−4 3  Productivity improves 75%  = = .75  4  4  Problem 3:

Using the new paint

Currently Labor

12 hrs * $10 = $120

12 hrs * $10 = $ 120

Material

240 * $3.50 = $840

360 * $3.50 = $1260

Supplies

= $ 20

=$

20

Energy

=$

=$

4

Total Inputs

= $984

Productivity

240/984 = 0.24

4

= $1404 360/1404 = .26

Problem 4:

If the material costs increase by $0.50 per doll:

Using the new paint Labor

12 hrs * $10 = $ 120

Material

360 * $4.00

= $1440

Supplies

=$

20

Energy

=$

4

Total Inputs

= $1584

Productivity

360/1584 = 0.23

Problem 5:

From the answer to Problem 3 we know the following:

Using the new paint

Currently Labor

12 hrs * $10 = $120

12 hrs * $10 = $ 120

Material

240 * $3.50 = $840

360 * $3.50 = $1260

Supplies

= $ 20

=$

20

Energy

=$ 4

=$

4

Total Inputs

= $984

= $1404

Productivity

240/984 = 0.24

360/1404 = .26

We want to know how high the material cost could go, using the new paint, before the productivity drops to the current level of 0.24. In mathematical terms we make the material cost a variable (X), set the new multifactor productivity value to the current level, 0.24, and solve for X.

360/(($12x10) + 360 $(X) + $20 + $4) = 0.24 360 = 0.24($120 + 360$(X) + $20 + $4) 360 = $28.8 + 86.4$(X) + $4.8 + $.96 325.44 = 86.4$(X) $(X)= 325.44/86.4 = $3.7666 ≅ $3.77

It follows then that the new paint could raise Materials cost by no more than approximately $0.27 (the difference between $3.77 and $3.50) before Ms. French would experience a decrease in multifactor productivity. Praktek Masalah: Bab 1, Operasi dan Produktivitas Masalah 1: Mance Fraily, Manajer Produksi di Ralts Mills, saat ini dapat mengharapkan operasi untuk menghasilkan 1000 meter persegi kain untuk setiap ton kapas mentah. Setiap ton kapas mentah membutuhkan jam kerja 5 untuk diproses. Ia percaya bahwa ia dapat membeli kapas yang lebih baik baku mutu, yang akan memungkinkan dia untuk menghasilkan 1.200 meter persegi per ton kapas mentah dengan jam kerja yang sama. Apa yang akan menjadi dampak pada produktivitas (diukur dalam meter persegi per tenaga kerja-jam) jika ia membeli kapas mentah berkualitas tinggi? Masalah 2:

CA Ratchet, mekanik mobil lokal, menemukan bahwa biasanya membawanya 2 jam untuk mendiagnosa dan memperbaiki masalah khas. Apa adalah produktivitas sehari-hari (asumsikan satu hari jam 8)? Mr Ratchet percaya bahwa dia dapat membeli perangkat komputer pemecahan masalah kecil, yang akan memungkinkan dia untuk menemukan dan memperbaiki masalah di luar biasa (setidaknya kepada pelanggannya!) Waktu 1 jam. Ia akan, bagaimanapun, harus menghabiskan satu jam ekstra setiap pagi menyesuaikan perangkat diagnostik komputerisasi. Apa yang akan menjadi dampak pada produktivitas jika ia membeli perangkat? Masalah 3: Joanna Prancis saat ini sedang bekerja total 12 jam per hari untuk memproduksi 240 boneka. Dia berpikir bahwa dengan mengubah cat digunakan untuk fitur wajah dan kuku bahwa dia dapat meningkatkan tingkat ke 360 boneka per hari. biaya bahan Total boneka masing-masing adalah sekitar $ 3,50; dia harus investasi $ 20 dalam persediaan yang diperlukan (Expendables) per hari, biaya energi diasumsikan hanya $ 4,00 per hari, dan ia berpikir ia harus membuat $ 10 per jam untuk waktunya. Melihat ini dari perspektif (multifaktor) produktivitas total, apa yang produktivitas nya pada saat ini dan dengan cat baru? Masalah 4: Bagaimana total (multifaktor) perubahan produktivitas olah menggunakan cat baru menaikan biaya bahan Ms Perancis dengan $ 0,50 per boneka? Masalah 5: Jika dia menggunakan cat baru, dengan apa yang bisa jumlah bahan Ms Perancis meningkatkan biaya tanpa mengurangi total (multifaktor) produktivitas?

Chapter 2, Operations Strategy in a Global Environment Problem 1: Identify how changes in the external environment may affect the OM strategy for a company. For example, what impact are the following factors likely to have on OM strategy? a. The occurrence of a major storm or hurricane. b. Terrorist attacks of 9/11/01. c. The much discussed decrease in the quality of American primary and secondary school systems. d. Trade Legislation such as WTO and NAFTA and changes in tariffs and quotas. e. The rapid rate at which the cost of health insurance is increasing.

f. The Internet.

Problem 2: Identify how the changes in the internal environment affect the OM strategy for a company. For example, what impact are the following factors likely to have on OM strategy? a. The increased use of Local and Wide Area Networks (LANs and WANs) b. An increased emphasis on service c. The increased role of women in the workplace d. The seemingly increasing rate at which both internal and external environments change.

Problem 3: Operations managers are called upon to support the organization's strategy. OM does this with some combination of one of three strategies. What are these three strategies?

ANSWERS:

Problem 1: a. A major storm or hurricane may have considerable impact on a company’s facilities and scheduling. Flooding and wind damage can make a facility unusable or significantly reduce its capacity. Stocks of raw materials, especially agricultural products, might be damaged or in short supply. The long-term availability of some materials might be significantly reduced. There may be a shortage of important services during the recovery. For example, the demand for roofers and builders is high after a major storm and they would like to be able to rapidly increase their capacity to handle the higher demand. b. Terrorist activity has forced organizations to rethink, and in many cases expand, their security systems. Firms have also had to reevaluate their supply networks and consider increasing their inventory safety stock. They may also reassess the risks of foreign locations and expansion. c. A decrease in the skill levels of Americans entering the labor market requires that organizations place more emphasis on training, turn to automation to obviate the need for human labor, and hire from outside the United States. d. WTO and NAFTA changed the rules for trading, opened new markets, and in some instances, changed the role of labor versus capital (where labor is especially low cost, emphasis often shifts from the use of capital to the use of labor).

e. The increasing cost of health insurance adds significantly to the cost of labor. Some large US organizations are passing on this increased cost to the employees or reducing other parts of the benefit package in response to these pressures. f. The Internet has promoted globalization of markets, and eliminated barriers of geography and time.

Problem 2: a. The increased use of LANs and WANs has, among other things, enabled new organizational structures, the movement of the locus of responsibility further down the organizational hierarchy (elimination of middle management), and the increasing practicality of JIT operations, mass customization, etc.. b. The increased emphasis on service has, among other things, fostered an increased information or information technology content of many products. Firms are also increasing training because so much of the service economy is dependent upon individual competence. c. The increased role of women in the workplace is requiring an increased emphasis on the creation and communication of appropriate human resource policies. It may also be fostering the creation of flexible work schedules and, to a lesser degree, telecommuting. d. Some companies seem to be adopting the perspective that their main problem is now the “management of change” as opposed to the management of a specific process or product. If nothing else, the management of change is becoming a formal part of the manager’s responsibility.

Problem 3: OM managers support the firm's strategy by achieving a competitive advantage through some combination of differentiation, low-cost leadership, and response.

Praktek Masalah: Bab 2, Strategi Operasi dalam Lingkungan Global Masalah 1: Mengidentifikasi bagaimana perubahan dalam lingkungan eksternal dapat mempengaruhi strategi OM bagi perusahaan. Misalnya, apa dampak faktor-faktor berikut mungkin memiliki strategi OM? a. Terjadinya badai besar atau badai. b. Serangan teroris dari 9/11/01. c. Penurunan banyak dibahas dalam kualitas Amerika sistem sekolah dasar dan menengah. d. Legislasi perdagangan seperti WTO dan NAFTA dan perubahan tarif dan kuota. e. Tingkat cepat di mana biaya asuransi kesehatan meningkat. f. Internet.

Masalah 2: Mengidentifikasi bagaimana perubahan dalam lingkungan internal mempengaruhi strategi OM bagi perusahaan. Misalnya, apa dampak faktor-faktor berikut mungkin memiliki strategi OM? a. Peningkatan penggunaan Lokal dan Wide Area Network (LAN dan WAN) b. Peningkatan penekanan pada pelayanan c. Peningkatan peran perempuan di tempat kerja d. Tingkat tampaknya meningkat di mana kedua perubahan lingkungan internal dan eksternal. Masalah 3: manajer Operasi dihimbau untuk mendukung strategi organisasi. OM melakukan hal ini dengan beberapa kombinasi salah satu dari tiga strategi. Apa ketiga strategi?

Chapter 3, Project Management Problem 1: The following represent activities in a major construction project. Draw the network to represent this project.

Activity

Immediate Predecessor

A

-

B

-

C

A

D

B

E

B

F

C, E

G

D

H

F, G

Problem 2: Given the following Time Chart and Network Diagram, find the Critical Path.

Activity

a

m

b

t

Variance

A

2

3

4

3

1/9

B

1

2

3

2

1/9

C

4

5

12

6

16/9

D

1

3

5

3

4/9

E

1

2

3

2

1/9

Problem 3: What is the variance in completion time for the critical path found in Problem 2?

Problem 4: A project has an expected completion time of 40 weeks and a standard deviation of 5 weeks. It is assumed that the project completion time is normally distributed. (a) What is the probability of finishing the project in 50 weeks or less? (b) What is the probability of finishing the project in 38 weeks or less? (c) The due date for the project is set so that there is a 90% chance that the project will be finished by this date. What is the date?

Problem 5: Development of a new deluxe version of a particular software product is being considered. The activities necessary for the completion of this project are listed in the table below along with their costs and completion times in weeks.

Activity

Normal Time

Crash Time

Normal Cost

Crash Cost

Immediate Predecessor

A

4

3

2,000

2,600

-

B

2

1

2,200

2,800

A

C

3

3

500

500

A

D

8

4

2,300

2,600

A

E

6

3

900

1,200

B, D

F

3

2

3,000

4,200

C, E

G

4

2

1,400

2,000

F

(a) What is the project expected completion date? (b) What is the total cost required for completing this project on normal time? (c) If you wish to reduce the time required to complete this project by 1 week, which activity should be crashed, and how much will this increase the total cost?

ANSWERS:

Problem 1:

Problem 2: Critical path: ACDE = 14

Problem 3:

Total

=∑ variance

variances of activities on critical path

Total variance = 1/ 9 + 16 / 9 + 4 / 9 + 1/ 9 = 2 2 / 9 = 2.55

And σ = 2.55 = 1.6

Problem 4:

5040 µ X Z2 5σ === −− (a) Therefore:

≤=≤= PP (X50)(Z2)0.97725

Z0.4 5µ X2 σ ===− −− (b)

Therefore:

≤=≤−= P (X38)P(Z0.4)0.34458

(c) 90% ≥ Z = 1.28 = (χ - µ ) / σ = χ − 40 / 5 Therefore:

= χ+= 1.28*54046.4weeks

Problem 5:

(a)

Project completion time is therefore t A + t D + t E + t F + t G = 4 + 8 + 6 + 3 + 4 = 25 (b) Total cost = $2, 000 + $2200 + $500 + $2,300 + $900 + $3, 000 + $1, 400 = $12, 300

$75 $2,600$2,300$300 − 844 ==

(c) Crash D 1 week at an additional cost of

Terjemahaan Soal Praktek: Bab 3, Manajemen Proyek

Masalah 1: Berikut mencerminkan aktivitas dalam proyek konstruksi besar. Menggambar jaringan untuk mewakili proyek ini. Kegiatan Segera Pendahulu ABCA DB EB F C, E GD H F, G

Masalah 2: Mengingat Waktu berikut Chart dan Network Diagram, menemukan Jalur Kritis. Kegiatan m a t b Varians A23431/9 B12321/9 C 4 5 12 6 16 / 9 D13534/9 E12321/9

Masalah 3: Apakah varians waktu penyelesaian untuk jalur kritis ditemukan pada Soal 2? Masalah 4: Sebuah proyek memiliki waktu penyelesaian yang diharapkan dari 40 minggu dan deviasi standar 5 minggu. Diasumsikan bahwa waktu penyelesaian proyek terdistribusi secara normal. (A) Berapakah probabilitas penyelesaian proyek dalam 50 minggu atau kurang? (B) Berapakah probabilitas penyelesaian proyek dalam 38 minggu atau kurang? (C) Tanggal jatuh tempo untuk proyek diatur sehingga ada kemungkinan 90% bahwa proyek akan selesai pada tanggal ini. Apa tanggal?

Masalah 5: Pengembangan versi deluxe baru dari produk perangkat lunak tertentu sedang

dipertimbangkan. Kegiatan yang diperlukan untuk penyelesaian proyek ini tercantum dalam tabel di bawah ini bersama dengan biaya mereka dan waktu selesai pada minggu. Kegiatan Waktu Normal Crash Normal Crash Time Cost Biaya Pendahulu Segera A 4 3 2.000 2.600 B 2 1 2.200 2.800 A C 3 3 500 500 A D 8 4 2.300 2.600 A E 6 3 900 1200 B, D F 3 2 3.000 4.200 C, E G 4 2 1.400 2.000 F (A) Apakah proyek diharapkan tanggal penyelesaian? (B) Berapakah total biaya yang dibutuhkan untuk menyelesaikan proyek ini pada waktu normal? (C) Jika Anda ingin mengurangi waktu yang dibutuhkan untuk menyelesaikan proyek ini dengan 1 minggu, kegiatan yang harus jatuh, dan berapa banyak ini akan meningkatkan biaya total?

Chapter 4, Forecasting Problem 1: Auto sales at Carmen’s Chevrolet are shown below. Develop a 3-week moving average. Week

Auto Sales

1

8

2

10

3

9

4

11

5

10

6

13

7

-

Problem 2:

Carmen’s decides to forecast auto sales by weighting the three weeks as follows: Weights Applied

Period

3

Last week

2

Twoweeks ago

1

Three weeks ago

6

Total

Problem 3: A firm uses simple exponential smoothing with α = 0.1 to forecast demand. The forecast for the week of January 1 was 500 units whereas the actual demand turned out to be 450 units. Calculate the demand forecast for the week of January 8.

Problem 4: Exponential smoothing is used to forecast automobile battery sales. Two value of α are examined, α = 0.8 and α = 0.5. Evaluate the accuracy of each smoothing constant. Which is preferable? (Assume the forecast for January was 22 batteries.) Actual sales are given below: Month

Actual Forecast Battery Sales

January

20

February 21 March

15

April

14

May

13

June

16

22

Problem 5: Use the sales data given below to determine: (a) the least squares trend line, and (b) the predicted value for 2003 sales. Year

Sales (Units)

1996

100

1997

110

1998

122

1999

130

2000

139

2001

152

2002

164

To minimize computations, transform the value of x (time) to simpler numbers. In this case, designate year 1996 as year 1, 1997 as year 2, etc.

Problem 6: Given the forecast demand and actual demand for 10-foot fishing boats, compute the tracking signal and MAD. Year Forecast Actual Demand Demand 1

78

71

2

75

80

3

83

101

4

84

84

5

88

60

6

85

73

Problem: 7

Over the past year Meredith and Smunt Manufacturing had annual sales of 10,000 portable water pumps. The average quarterly sales for the past 5 years have averaged: spring 4,000, summer 3,000, fall 2,000 and winter 1,000. Compute the quarterly index.

Problem: 8 Using the data in Problem, Meredith and Smunt Manufacturing expects sales of pumps to grow by 10% next year. Compute next year’s sales and the sales for each quarter.

ANSWERS:

Problem 1:

Moving average =

∑ demand in previous n periods n

Week

Auto Sales

Three-Week Average

Moving

1

8

2

10

3

9

4

11

(8 + 9 + 10) / 3 = 9

5

10

(10 + 9 + 11) / 3 = 10

6

13

(9 + 11 + 10) / 3 = 10

7

-

(11 + 10 + 13) / 3 = 11 1/3

Problem 2:

Weighted moving average =

∑ (weight for period n)(demand in period n) ∑ weights

Week

Auto Sales

Three-Week Moving Average

1

8

2

10

3

9

4

11

[(3*9) + (2*10) + (1*8)] / 6 = 9 1/6

5

10

[(3*11) + (2*9) + (1*10)] / 6 = 10 1/6

6

13

[(3*10) + (2*11) + (1*9)] / 6 = 10 1/6

7

-

[(3*13) + (2*10) + (1*11)] / 6 = 11 2/3

Problem 3:

Ft = Ft −1 + α(A t −1 − Ft −1 ) = 500 + 0.1( 450 − 500) = 495 units

Problem 4: Month

Actual Battery Sales

Rounded Forecast with a =0.8

Absolute Deviation with a =0.8

Rounded Forecast with a =0.5

Absolute Deviation with a =0.5

January

20

22

2

22

2

February

21

20

1

21

0

March

15

21

6

21

6

April

14

16

2

18

4

May

13

14

1

16

3

June

16

13

3

14.5

1.5

SE

S = 15

S = 16

2.56

2.95

3.5

3.9

On the basis of this analysis, a smoothing constant of a = 0.8 is preferred to that of a = 0.5 because it has a smaller MAD.

Problem 5: Year

Time Period (X)

Sales (Units) (Y)

X2

XY

1996

1

100

1

100

1997

2

110

4

220

1998

3

122

9

366

1999

4

130

16

520

2000

5

139

25

695

2001

6

152

36

912

2002

7

164

49

1148

S X = S Y S S XY 28 =917 X2=140 = 3961

x=

∑ x = 28 = 4

y=

∑ y = 917 = 131

n

n

7

7

b=

∑ xy − nx. y = 3961 − 7.4.131 = 293 = 10.46 28 140 − 7.4 ∑ x − nx 2

2

2

a = y − bx = 131 − (10.46 × 4) = 89.16 Therefore, the least squares trend equation is:

y$ = a + bx = 89.16 + 10.46 x To project demand in 2003, we denote the year 2003 as x = 8, and: Sales in 2003 = 89.16 + 10.46 * 8 = 172.84

Problem 6: Year Forecast Actual Error RSFE Demand Demand 1

78

71

-7

-7

2

75

80

5

-2

3

83

101

18

16

4

84

84

0

16

5

88

60

-28

-12

6

85

73

-12

-24

∑ Forecast errors

=

MAD =

n

70 = 11.7 6

Year Forecast Actual |Forecast Cumulative MAD Tracking Demand Demand Error| Error Signal 1

78

71

7

7

7.0

-1.0

2

75

80

5

12

6.0

-0.3

3

83

101

18

30

10.0

+1.6

4

84

84

0

30

7.5

+2.1

5

88

60

28

58

11.6

-1.0

6

85

73

12

70

11.7

-2.1

Tracking Signal =

RFSE −24 = = 2.1 MADs MAD 11.7

Problem 7: Sales of 10,000 units annually divided equally over the 4 seasons is 10,000 / 4 = 2,500 and the seasonal index for each quarter is: spring 4,000 / 2,500 = 1.6; summer 3,000 / 2,500 = 1.2; fall 2,000 / 2,500 =.8; winter 1,000 / 2,500 =.4.

Problem 8: Next years sales should be 11,000 pumps (10,000 * 110 . = 11,000). Sales for each quarter should be 1/4 of the annual sales * the quarterly index.

Spring = (11,000 / 4) *1.6 = 4,400; Summer = (11,000 / 4) *1.2 = 3,300; Fall = (11,000 / 4) *.8 = 2,200; Winter = (11,000 / 4) *.4.= 1,100.

Praktek Masalah: Bab 4, Peramalan Masalah 1: Penjualan mobil di Carmen Chevrolet ditunjukkan di bawah ini. Mengembangkan rata-rata 3 minggu bergerak. Minggu Auto Penjualan 18 2 10 39 4 11 5 10 6 13 7Masalah 2: Carmen memutuskan untuk meramalkan penjualan mobil dengan bobot tiga minggu sebagai berikut: Berat Terapan Periode 3 Minggu lalu 2 Twoweeks lalu 1 Tiga minggu yang lalu 6 Jumlah Masalah 3: perusahaan A menggunakan pemulusan eksponensial sederhana dengan untuk meramalkan

permintaan. Ramalan untuk minggu 1 Januari 500 unit sedangkan permintaan aktual ternyata menjadi 450 unit. Hitung perkiraan permintaan untuk minggu Januari 8. Masalah 4: Pemulusan eksponensial digunakan untuk meramalkan penjualan mobil baterai. Dua nilai yang diperiksa, dan evaluasi atas keakuratan setiap konstanta. Mana yang lebih baik? (Asumsikan meramalkan bulan Januari adalah 22 baterai.) Penjualan aktual diberikan di bawah ini: Bulan Penjualan Baterai Aktual Forecast 20 Jan 22 21 Februari 15 Maret April 14 13 Mei 16 Juni

Masalah 5: Gunakan data penjualan yang diberikan di bawah untuk menentukan: (a) garis tren kuadrat sedikit, dan (b) nilai prediksi untuk tahun 2003 penjualan. Tahun Penjualan (Unit) 1996 100 1997 110 1998 122 1999 130 2000 139 2001 152 2002 164 Untuk meminimalkan perhitungan, mengubah nilai x (waktu) ke nomor sederhana. Dalam hal ini, menetapkan tahun 1996 sebagai tahun 1, 1997 sebagai tahun 2, dll

Masalah 6: Mengingat peramalan permintaan dan permintaan sebenarnya untuk kapal nelayan 10-kaki, menghitung sinyal pelacakan dan MAD. Tahun Prakiraan Aktual Permintaan Permintaan 1 78 71 2 75 80 3 83 101 4 84 84 5 88 60 6 85 73 Masalah: 7 Selama tahun lalu Meredith dan Smunt Manufaktur memiliki penjualan tahunan sebesar 10.000 pompa air portabel. Penjualan rata-rata kuartalan selama 5 tahun terakhir memiliki rata-rata: 4.000 musim semi, musim panas 3000, musim gugur dan musim dingin 2.000 1.000. Hitung indeks triwulanan. Soal: 8

Menggunakan data pada Soal, Meredith dan Smunt Manufaktur mengharapkan penjualan pompa untuk tumbuh sebesar 10% tahun depan. Hitung tahun depan penjualan dan penjualan untuk setiap kuartal.

Chapter 5, Design of Goods and Services Problem 1: You wish to compete in the super premium ice cream market. The task is to determine the wants of the super premium market and the attributes/hows to be met by their firm. Use the house of quality concept. Market research has revealed that customers feel four factors are significant in making a buying decision. A “rich” taste is most important followed by smooth texture, distinct flavor, and a sweet taste. From a production standpoint, important factors are the sugar content, the amount of butterfat, low air content, and natural flavors. Problem 2: Prepare a bill-of-material for a ham and cheese sandwich. Problem 3: Prepare an assembly chart for a ham and cheese sandwich.

Problem 4: Michael’s Engineering, Inc. manufactures components for the ever-changing notebook computer business. He is considering moving from a small custom design facility to an operation capable of much more rapid design of components. This means that Michael must consider upgrading his CAD equipment. Option 1 is to purchase two new desktop CAD systems at $100,000 each. Option 2 is to purchase an integrated system and the related server at $500,000. Michael’s sales manager has estimated that if the market for notebook computers continues to expand, sales over the life of either system will be $1,000,000. He places the odds of this happening at 40%. He thinks the likelihood of the market having already peaked to be 60% and future sales to be only $700,000. What do you suggest Michael do and what is the EMV of this decision?

ANSWERS:

Problem 1:

One possible solution for this problem is:

Problem 2:

One possible BOM would be:

Bill of Material Bread

2 slices

Ham

1 slice

Swiss Cheese

1 slice

Lettuce

1/26 head of lettuce

Mustard

2 teaspoon

Pickle relish

1 teaspoon

Paper plate

1

Paper napkin

1

Problem 3:

Based on the BOM in Problem 2, an assembly chart might look like:

Problem 4:

The EMV for the desktop systems is $620,000 vs. $320,000 for the integrated system. Therefore, Michael should purchase the desktop systems.

Praktek Masalah: Bab 5, Desain Barang dan Jasa Masalah 1: Anda ingin bersaing di pasar es krim super premium. Tugas kita adalah untuk menentukan keinginan pasar super premium dan atribut / hows yang harus dipenuhi oleh perusahaan mereka. Gunakan rumah konsep kualitas. Penelitian pasar telah mengungkapkan bahwa pelanggan merasa empat faktor yang signifikan

dalam membuat keputusan pembelian. Sebuah "kaya" rasa yang paling penting diikuti oleh tekstur yang halus, aroma yang berbeda, dan rasa manis. Dari sudut pandang produksi, faktor penting adalah isi gula, jumlah Lemak mentega, kandungan udara yang rendah, dan rasa alami. Masalah 2: Siapkan tagihan-of-bahan untuk sandwich ham dan keju. Masalah 3: Siapkan bagan perakitan untuk sandwich ham dan keju. Masalah 4: Michael Rekayasa, Inc memproduksi komponen untuk usaha notebook selalu berubah komputer. Dia mempertimbangkan untuk pindah dari fasilitas desain kecil kustom untuk operasi mampu jauh lebih cepat desain komponen. Ini berarti bahwa Michael harus mempertimbangkan untuk mengupgrade-nya peralatan CAD. Opsi 1 adalah untuk membeli dua baru sistem desktop CAD pada $ 100.000. Opsi 2 adalah dengan membeli sistem yang terintegrasi dan server terkait di $ 500.000. manajer penjualan Michael memperkirakan bahwa jika pasar untuk komputer notebook terus berkembang, penjualan selama umur sistem baik akan menjadi $ 1.000.000. Dia menempatkan kemungkinan hal ini terjadi pada 40%. Dia pikir kemungkinan pasar karena telah memuncak menjadi 60% dan penjualan masa depan hanya $ 700.000. Apa yang anda sarankan Michael lakukan dan apa EMV dari keputusan ini?

Chapter 6, Managing Quality Problem 1: The accounts receivable department has documented the following defects over a 30-day period:

Category Invoice amount does not agree with the check amount Invoice not on record (not found) No formal invoice issued Check (payment) not received on time Check not signed Invoice number and invoice referenced do not agree

Frequency 108 24 18 30 8 12

What techniques would you use and what conclusions can you draw about defects in the accounts receivable department?

Problem 2: Prepare a flow chart for purchasing a Big Mac at the drive-through window at McDonalds.

Problem 3: Draw a fishbone chart detailing reasons why a part might not be correctly machined. ANSWERS:

Problem 1:

Category Invoice amount does not agree with the check amount Invoice not on record (not found) No formal invoice issued Check (payment) not received on time Check not signed Invoice number and invoice referenced do not agree

Frequency 108 24 18 30 8 12 =

200

Percent 54 12 9 15 4 6 100

Use a Pareto chart to organize the defects and conclude that the obvious problem (about half the defects) is the failure of the check to agree with the company’s records as to the correct amount. Other problems are late payments and an apparent invoice-filing problem in the office. Notice that 27% of these common errors appear to be the result of procedural problems within accounts receivable (invoice not on record, no invoice issued, and invoice numbering problems). This value could be considerably higher depending on how much of the problem of disagreement between invoice and check amounts is the result of accounts receivable process problems.

Problem 2:

Distance --

Symbol

Activity Pull up to speaker

--

Press button

--

Wait for response

--

Verbalize order

--

Get confirmation of order and cost

20

Move car up in line

--

Wait

20

Move car up in line

--

Wait

--

Verify order and cost

--

Pay and receive order

--

Leave

--

Realize they forgot the extra catsup!

Problem 3

Praktek Masalah: Bab 6, Mengelola Kualitas Masalah 1: Departemen Piutang telah mendokumentasikan cacat berikut selama periode 30-hari: Kategori Frekuensi Faktur jumlah tidak setuju dengan jumlah cek 108 Faktur tidak pada catatan (tidak ditemukan) 24 Tidak ada faktur resmi yang dikeluarkan 18 Periksa (pembayaran) tidak diterima pada waktu 30 Periksa tidak ditandatangani 8 Faktur dan nomor faktur direferensikan tidak setuju 12 Teknik apa yang akan Anda gunakan dan apa kesimpulan yang dapat Anda menarik tentang cacat di departemen piutang? Masalah 2: Siapkan diagram alur untuk membeli Big Mac di drive-through window di McDonalds.

Masalah 3: Menggambar diagram tulang ikan merinci alasan mengapa sebagian mungkin tidak benar mesin.

Chapter 7, Process Strategy Problem 1: Jackson Custom Machine Shop has a contract for 130,000 units of a new product. Sam Jumper, the owner, has calculated the cost for three process alternatives. Fixed costs will be: for general-purpose equipment (GPE), $150,000; flexible manufacturing (FMS), $350,000; and dedicated automation (DA), $950,000. Variable costs will be: GPE, $10; FMS, $8; and DA, $6. Which should he choose?

Problem 2: Solve Problem 1 graphically Problem 3: Using either your analytical solution found in Problem 1, or the graphical solution found in Problem 2, identify the volume ranges where each process should be used.

Problem 4: If Jackson Custom Machine is able to convince the customer to renew the contract for another one or two years, what implications does this have for his decision?

ANSWERS: Problem 1: Solve for the crossover between GPE and FMS:

10X + 150000 = 8X + 350000 or

2X = 200000 x = 100,000 units Solve for the crossover between FMS and DA:

8X + 350000 = 6X + 950000 or

2X = 600000 X = 300000 Therefore, at a volume of 130,000 units, FMS is the appropriate strategy. Problem 2 & 3:

Below 100,000 units use GPE, between 100,000 and 300,000 use FMS, above 300,000 use DA Problem 4: If Jackson Custom Machine is able to get the customer to extend the contract for another two years, the owner would certainly wish to take advantage of the savings using Dedicated Automation. Praktek Masalah: Bab 7, Proses Strategi Masalah 1: Jackson Custom Machine Shop memiliki kontrak untuk 130.000 unit produk baru. Sam Jumper, pemilik, telah menghitung biaya untuk tiga alternatif proses. Biaya tetap akan: untuk peralatan keperluan umum (EPG), $ 150.000; manufaktur fleksibel (FMS), $ 350.000, dan otomatisasi khusus (DA), $ 950.000. Biaya variabel akan: EPG, $ 10; FMS, $ 8; dan DA, $ 6. Yang mana yang harus dia pilih? Masalah 2: Mengatasi Masalah 1 grafis Masalah 3: Baik menggunakan solusi analitis Anda ditemukan pada Soal 1, atau solusi grafis yang ditemukan pada Soal 2, mengidentifikasi volume berkisar di mana masing-masing proses harus digunakan. Masalah 4: Jika Jackson Custom Mesin mampu meyakinkan pelanggan untuk memperbaharui kontrak

selama satu atau dua tahun, apa implikasi hal ini miliki untuk keputusannya?

Chapter 8, Location Strategies Problem 1: A major drug store chain wishes to build a new warehouse to serve the whole Midwest. At the moment, it is looking at three possible locations. The factors, weights, and ratings being considered are given below:

Ratings Factor

Weights

Peoria

Des Moines

Chicago

20

4

7

5

Labor cost

5

8

8

4

Taxes

15

8

9

7

Nearness to suppliers

10

10

6

10

Nearness markets

to

Which city should they choose? Problem 2: Balfour’s is considering building a plant in one of three possible locations. They have estimated the following parameters for each location:

Location

Fixed Cost

Variable Cost

Waco, Texas

$300,000

$5.75

Tijuana, Mexico

$800,000

$2.75

Fayetteville, Arkansas

$100,000

$8.00

For what unit sales volume should they choose each location? Problem 3:

Our main distribution center in Phoenix, AZ is due to be replaced with a much larger, more modern facility that can handle the tremendous needs that have developed with the city’s growth. Fresh produce travels to the seven store locations several times a day making site selection critical for efficient distribution. Using the data in the following table, determine the map coordinates for the proposed new distribution center.

Store Locations

Map Coordinates (x,y)

Truck Round Trips per Day

Mesa

(10,5)

3

Glendale

(3,8)

3

Camelback

(4,7)

2

Scottsdale

(15,10)

6

Apache Junction

(13,3)

5

Sun City

(1,12)

3

Pima

(5,5)

10

Problem 4: A company is planning on expanding and building a new plant in one of three countries in Middle or Eastern Europe. The general manager, Patricia Donegal, has decided to base her decision on six critical success factors: technology availability and support, availability and quality of public education, legal and regulatory aspects, social and cultural aspects, economic factors, and political stability. Using a rating system of 1 (least desirable) to 5 (most desirable) she has arrived at the following ratings (you may, of course, have different opinions). In which country should the plant be built?

Critical Success Factor

Turkey

Serbia

Slovakia

Technology availability and support

4

3

4

Availability and quality of public education

4

4

3

Legal and regulatory aspects

2

4

5

Social and cultural aspects

5

3

4

Economic factors

4

3

3

Political stability

4

2

3

Problem 5: Assume that Patricia decides to use the following weights for the critical success factors:

Technology availability and support

0.3

Availability and quality of public education

0.2

Legal and regulatory aspects

0.1

Social and cultural aspects

0.1

Economic factors

0.1

Political stability

0.2

Would this change her decision? Problem 6:

Patricia’s advisors have suggested that Turkey and Slovakia might be better differentiated by either (a) doubling the number of critical success factors, or (b) breaking down each of the existing critical success factors into smaller, more narrowly defined items, e.g., Availability and quality of public education might be broken into primary, secondary, and post-secondary education. How would you advise Ms. Donegal?

ANSWERS: Problem 1:

Ratings

Weighted Ratings

Weights

Peoria

Des Moines

Chicago

Peoria

Des Moines

Chicago

Nearness to markets

20

4

7

5

80

140

100

Labor cost

5

8

8

4

40

40

20

Taxes

15

8

9

7

120

135

105

Nearness to suppliers

10

10

6

10

100

60

100

Sum of Weighted ratings:

340

375

325

Factor

Therefore, it appears that based upon the weights and rating, Des Moines should be chosen. Problem 2: Transition between Waco and Tijuana:

300, 000 + (5.75 x) = 800, 000 + (2.75 x) 3x = 500, 000 x = 166,000 Transition between Waco and Fayetteville:

300, 000 + (5.75 x ) = 100, 000 + (8.00 x ) 200, 000 = 2.25 x 88,888 = x

Problem 3: New Distribution Center should be located at:

Cx =

(10*3) + (3*3) + (4* 2) + (15* 6) + (13*5) + (1*3) + (5*10) 255 = = 7.97 3 + 3 + 2 + 6 + 5 + 3 + 10 32

Cy =

(5*3) + (8*3) + (7 * 2) + (10 * 6) + (3*5) + (12*3) + (5*10) 214 = = 6.69 3 + 3 + 2 + 6 + 5 + 3 + 10 32

Problem 4:

Critical Success Factor

Turkey

Serbia

Slovaki a

4

3

4

4

4

3

Legal and regulatory aspects

2

4

5

Social and cultural aspects

5

3

4

Economic factors

4

3

3

Political stability

4

2

3

23

19

22

Technology availability and support Availability education

and

quality

of

public

=

Based upon her ratings of the critical success factors, Patricia should choose Turkey. From a practical perspective, given the small difference between the scores for Turkey and Slovakia, and the subjectivity of the ratings themselves, Patricia would be better advised to develop additional critical success factors, more carefully weigh the individual factors; or, in general, to acquire more information before making her decisions.

Problem 5:

Critical Success Factor

Wgt

Turkey

Technology availability and support

0.3

4

1.2

3

0.9

4

1.2

Availability and quality of public education

0.2

4

0.8

4

0.8

3

0.6

Legal and regulatory aspects

0.1

2

0.2

4

0.4

5

.5

Serbia

Slovaki a

Social and cultural aspects

0.1

5

0.5

3

0.3

4

0.4

Economic factors

0.1

4

0.4

3

0.3

3

0.3

Political stability

0.2

4

0.8

2

0.4

3

0.6

= 3.9

3.1

3.6

No, in this case, use of the weighting factors does not change the recommendation. One might again suggest that additional information be considered in making the decision. Problem 6: (a) Doubling the number of critical success factors. There are two issues here. First, from a practical perspective there are a limited number of truly “critical” success factors – and these should be the ones presently being considered. Any additional factors should be of secondary or tertiary importance. Second, given the subjective nature of the rating process, adding additional factors would also increase the overall margin of error of the final ratings to a degree that may eliminate any gain in differentiation arising from the use of the additional factors. The use of a maximum of seven to nine critical success factors is usually appropriate. (b) Given that one’s ability to estimate or rate an aggregate is usually better than one’s ability to estimate or rate the individual components of the aggregate, this approach is unlikely to provide much help. Praktek Masalah: Bab 8, Strategi Lokasi Masalah 1: Sebuah jaringan toko obat utama ingin membangun sebuah gudang baru untuk melayani seluruh Midwest. Pada saat ini, adalah melihat tiga lokasi mungkin. Faktor, bobot, dan peringkat yang dianggap diberikan di bawah ini: Ratings Faktor Berat Peoria Des Moines Chicago Kedekatan dengan pasar 20 4 7 5 Biaya tenaga kerja 5 8 8 4 Pajak 15 8 9 7 Kedekatan dengan pemasok 10 10 6 10 Kota mana yang harus mereka pilih? Masalah 2: Balfour sedang mempertimbangkan membangun pabrik di salah satu dari tiga lokasi mungkin. Mereka telah memperkirakan parameter berikut ini untuk setiap lokasi: Lokasi Biaya Tetap Biaya Variabel

Waco, Texas $ 300,000 $ 5,75 Tijuana, Mexico $ 800,000 $ 2,75 Fayetteville, Arkansas $ 100,000 $ 8,00 Untuk apa penjualan unit volume harus mereka memilih setiap lokasi? Masalah 3: utama distribusi kami pusat di Phoenix, AZ adalah karena diganti dengan fasilitas, jauh lebih besar yang lebih modern yang dapat menangani kebutuhan luar biasa yang telah dikembangkan dengan pertumbuhan kota. Produk segar perjalanan ke tujuh lokasi toko beberapa kali sehari membuat pilihan lokasi yang kritis untuk distribusi yang efisien. Menggunakan data dalam tabel berikut, tentukan peta koordinat untuk pusat distribusi baru yang diusulkan. Peta Lokasi Toko Koordinat (x, y) Perjalanan Bundar Truk per Hari Mesa (10,5) 3 Glendale (3,8) 3 Camelback (4,7) 2 Scottsdale (15,10) 6 Apache Junction (13,3) 5 Sun City (1,12) 3 Pima (5,5) 10

Masalah 4: Sebuah perusahaan berencana memperluas dan membangun pabrik baru di salah satu dari tiga negara di Timur Tengah atau Eropa. Manajer umum, Patricia Donegal, telah memutuskan untuk mendasarkan keputusan di atas enam faktor keberhasilan kritis: ketersediaan dan dukungan teknologi, ketersediaan dan kualitas pendidikan masyarakat, aspek hukum dan peraturan, aspek sosial dan budaya, faktor ekonomi, dan stabilitas politik. Menggunakan sistem peringkat 1 (paling tidak diinginkan) sampai 5 (paling diinginkan) dia telah tiba di peringkat berikut (mungkin Anda, tentu saja, memiliki pendapat yang berbeda). Di negara mana harus menanam dibangun? Faktor Sukses Turki Kritis Serbia Slovakia Teknologi ketersediaan dan dukungan 4 3 4 Ketersediaan dan kualitas pendidikan masyarakat 4 4 3 Aspek hukum dan peraturan 2 4 5 Sosial dan aspek budaya 5 3 4 Faktor ekonomi 4 3 3 Stabilitas politik 4 2 3

Masalah 5: Asumsikan bahwa Patricia memutuskan untuk menggunakan bobot berikut untuk faktor keberhasilan kritis: Teknologi ketersediaan dan dukungan 0,3 Ketersediaan dan kualitas pendidikan publik 0,2

Aspek hukum dan peraturan 0,1 Sosial dan aspek budaya 0,1 Faktor-faktor ekonomi 0,1 Stabilitas politik 0,2 Apakah perubahan ini keputusannya?

Masalah 6: penasihat Patricia telah menyarankan bahwa Turki dan Slovakia mungkin lebih baik dibedakan oleh (a) dua kali lipat jumlah faktor keberhasilan kritis, atau (b) menguraikan setiap faktor kesuksesan yang ada kritis menjadi lebih kecil, item lebih sempit didefinisikan, misalnya, Ketersediaan dan kualitas pendidikan publik mungkin akan dibagi menjadi pendidikan primer, sekunder, dan pasca-sekolah menengah. Bagaimana Anda menyarankan Ms Donegal?

Chapter 9, Layout Strategy Problem 1: As in most kitchens, the baking ovens in Lori’s Kitchen in New Orleans are located in one area near the cooking burners. The refrigerators are located next to each other as are the dishwashing facilities. A work area of tabletops is set aside for cutting, mixing, dough rolling, and assembling of final servings, although different table areas may be reserved for each of these functions. Given the following Interdepartmental Activity Matrix, develop an appropriate layout for Lori’s Kitchen.

Interdepartmental Activity Matrix Cooking Burners (A)

Refrigerators (B)

Dishwashing (C)

Work Area (D)

-

7

193

12

-

4

82

-

222

Cooking burners (A) Refrigerator (B) Dishwashing (C) Work Area (D)

The present layout is:

-

A

B

with a distance of 10 feet between adjacent areas.

C

D

Computing the Load * Distance measure:

Load * Distance A to B

7 * 10

70

A to C

193*20

3860

A to D

12*30

360

B to C

4*10

40

B to D

82*20

1640

C to D

222*10

2220

Total

8190

Develop a preferred layout. What is the sum of the loads * distance of your new layout?

Problem 2: A firm must produce 40 units/day during an 8-hour workday. Tasks, times, and predecessor activities are given below.

Task

Time (Minutes)

Predecessor(s)

A

2

-

B

2

A

C

8

-

D

6

C

E

3

B

F

10

D, E

G

4

F

H

3

G

Total

38 minutes

Determine the cycle time and the appropriate number of workstations to produce the 40 units per day.

ANSWERS

Problem 1: From the Activity Matrix, C and D should be next to each other and A should be next to C. The other relationships are minor by comparison. One possible solution is:

B

A

C

D

with a distance of 10 feet between adjacent areas. Computing the Load * Distance measure:

Load * Distance A to B

7 * 10

70

A to C

193*10

1930

A to D

12*20

240

B to C

4*20

80

B to D

82*30

2460

C to D Total

222*10

2220 7000

Further improvement is possible. Try analyzing the following layouts.

A

C

B

D

A

C

D

B

Problem 2:

Cycle time =

Production time available 8 hrs *60 minutes/hr 480 = = = 12 minutes/cycle Units required 40 units 40

Minimum number of workstations = =

∑t

i

Cycle time

=

Work time required Cycle time

38 minutes = 3.17 station 12 minutes/cycle

3.17 workstations must be rounded up to 4 as 3 workstations would not be able to produce the required output. One layout – not necessarily optimal

Praktek Masalah: Bab 9, Strategi Layout Masalah 1: Seperti di dapur besar, oven kue di Dapur Lori di New Orleans terletak di satu area dekat pembakar memasak. Lemari pendingin yang terletak di sebelah satu sama lain sebagai adalah fasilitas pencuci piring. Sebuah wilayah kerja permukaan meja disisihkan untuk memotong, mencampur, rolling adonan, dan perakitan porsi akhir, meskipun daerah tabel yang berbeda dapat disediakan untuk masing-masing fungsi. Mengingat Antar berikut Aktivitas Matrix, mengembangkan tata letak yang sesuai untuk Lori's Kitchen. Kegiatan antar departemen Matrix Memasak Burners (A) Kulkas (B) Pencuci Piring (C) Wilayah Kerja (D) Memasak burner (A) - 7 193 12 Kulkas (B) - 4 82 Pencuci Piring (C) - 222 Area Kerja (D) Tata letak ini adalah: ABCD

dengan jarak 10 meter antara daerah sekitarnya.

Komputasi Load * Jarak mengukur: Load * Jarak A ke B 7 * 10 70 A ke C 193 * 20 3860 A * 12 sampai D 30 360 B ke C 4 * 10 40 B ke D 82 * 20 1640 C ke D 222 * 10 2220 Jumlah 8190

Mengembangkan tata letak disukai. Apa adalah jumlah jarak * banyak layout baru Anda?

Masalah 2: Sebuah perusahaan harus menghasilkan 40 unit / hari selama hari kerja 8-jam. Tugas, kali, dan kegiatan pendahulunya diberikan di bawah ini. Tugas Waktu (Menit) Pendahulu (s) A2B2A C8D6C E3B F 10 D, E G4F H3G Total 38 menit Tentukan waktu siklus dan jumlah yang tepat workstation untuk memproduksi 40 unit per hari.

Chapter 10. Human Resources and Job Design Problem 1: Develop a Process Chart for making a grilled cheese sandwich.

Problem 2: Develop an Activity Chart for doing three loads of laundry.

Problem 3: Develop a Process Chart for changing the oil in an automobile.

Problem 4: Develop an Activity Chart for writing a term paper.

ANSWERS

Problem 1: One possible solution. The level of detail in process charts depends upon the requirements of the job. Time is often included to aid analysis of value added. Process Chart Distance Symbol Process Description 10 Move to cabinet Get loaf of bread 6 Move to counter Open loaf of bread Remove two slices of bread Lay slices on counter-top Close loaf of bread Move to cabinet Replace loaf of bread on shelf 10 Move to refrigerator

Get mustard, package of ham from refrigerator, and butter 10 Move to counter Open package of ham Remove two slices of ham Close package of ham Open mustard Spread mustard on bread Close mustard Place ham on bread Close sandwich Open butter Spread butter on top slice of bread 5 Move to stove Get fry pan Turn heat on under fry pan Wait for pan to heat 5 Move to counter Get sandwich & butter 5 Move to stove

Place sandwich, buttered-side down in pan Butter top slice Close butter 5 Move to counter Pick up ham, mustard, and butter 10 Move to refrigerator Return butter, mustard, and ham to refrigerator 5 Move to stove Wait for sandwich to brown on bottom Inspect Flip sandwich Wait for sandwich to brown on bottom Inspect sandwich 10 Move to serving area Serve sandwich

Problem 2: Time

Operator

Machine 1

Machine 2

Washer

Dryer

Load clothes and detergent in to Machine 1

Being loaded

Idle

Idle

Run

Idle

Remove clothes from Machine 1

Being unloaded

Idle

Load clothes into Machine 2

Idle

Being loaded

Load clothes and detergent into Machine 1

Being loaded

Run

Idle

Run

Run

Remove clothes from Machine 2

Idle

Being unloaded

Hang clothes

Idle

Idle

Problem 3: One solution might be: Process Chart for Changing Oil in Car Distance Symbol 30

Check that needed filter is in stock Check that oil is in stock Move to car

Get into car -

Start engine Idle car to warm engine Drive car onto lift Stop engine Release hood catch

10

Get out of car Go to lift control Raise lift

10

Go to toolbox Get wrench Get container for drained oil Get rag

10 -

Walk under lift Wipe around oil drain plug Loosen oil drain plug Position container Remove oil drain plug

20 15

Drain oil Wipe around oil drain plug Replace oil drain plug Tighten oil drain plug Remove container to disposal area Move to lift control Lower lift Wipe oil from wrench

5

Move to toolbox Return wrench to tool chest Get oil filter wrench from tool chest Get container for drained oil

10 -

Move to car engine area Raise hood Find oil filter

-

Loosen oil filter Position container Remove oil filter

20

25

Take old filter and container of drained oil to disposal area Move to filter stock area Get new filter

25 -

Move to car engine area Wipe around filter mount oil seal Install new filter Tighten new filter Remove oil filler cap

40

Move to oil stock Get oil from stock Move to car engine compartment Open oil container; pour in oil filler Replace oil filler cap Clean hands Start engine Idle engine Stop engine Check oil level

Check oil filter seal Check oil drain plug Wipe up any spilled oil Take empty oil containers to disposal area Wipe oil from oil filter wrench 25

Return oil filter wrench to tool chest Start engine Drive car off lift Park car for owner pickup Return keys

Problem 4:

Activity Chart for Writing Term Paper Time

Operator

Computer 1

Computer 2

Desktop

Library

Develop topic

Used for word processing

Develop initial outline

Used for word processing

Research

Flesh out outline with information from research

Used for look-up and web search Used for word processing

Evaluate paper Final edit paper

Used for word processing

Proof read paper

Used for word processing

Print final copy of paper

Used for printing

Does this Activity Chart contain enough detail that you could estimate the time it would take to write the term paper?

Praktik Masalah: 10 Bab Sumber Daya Manusia dan Desain Kerja Masalah 1: Mengembangkan Chart Proses untuk membuat sandwich keju panggang. Masalah 2: Mengembangkan Chart Kegiatan untuk melakukan tiga banyak cucian.

Masalah 3: Mengembangkan Chart Proses untuk mengubah minyak di mobil. Masalah 4: Mengembangkan Chart Kegiatan untuk menulis makalah.

Chapter 11, Supply-Chain Management Problem 1: Determine the sales necessary to equal a dollar of savings on purchases for a company that has a net profit of 6% and spends 70% of its revenues on purchases. Problem 2: Determine the sales necessary to equal a dollar of savings on purchases for a company that has a net profit of 8% and spends 40% of its revenues on purchases. Problem 3 Phil Carter, President of Carter Computer Components, Corp. has the option of shipping computer transformers from its Singapore plant via container ship or airfreight. The typical shipment has a value of $75,000. A container ship takes 24 days and costs $5,000; airfreight takes 1 day and costs $8,000. Holding cost is estimated to be 40% in either case. How should shipments be made?

ANSWERS

Problem 1: From Table 11.3, we see that this company would have to increase sales by approximately $5.56 Problem 2: From Table 11.3, we see that this company would have to increase sales by approximately $2.94 Problem 3:

Cost via container ship:

[24 *

(.40 * 75,000) ] + 5,000 = (24 * 82.19) + 5,000 = 1,972.56 + 5,000 = $6,972.56 365

Cost via airfreight:

[1*

(.40 * 75,000) ] + 8,000 = (1* 82.19) + 8,000 = 82.19 + 8,000 = $8,082.19 365

Therefore, use the container ship as it has a lower total cost.

Bab 11, Supply-Chain Management Masalah 1: Tentukan penjualan yang diperlukan untuk sebesar satu dolar tabungan pada pembelian untuk perusahaan yang memiliki laba bersih sebesar 6% dan menghabiskan 70% dari pendapatan pada pembelian. Masalah 2: Tentukan penjualan yang diperlukan untuk sebesar satu dolar tabungan pada pembelian untuk perusahaan yang memiliki laba bersih sebesar 8% dan menghabiskan 40% dari pendapatan pada pembelian. Masalah 3 Phil Carter, Presiden Carter Komponen Komputer, Corp memiliki pilihan untuk pengiriman transformer komputer dari tanaman Singapura yang melalui kapal kontainer atau udara. Pengiriman khas memiliki nilai sebesar $ 75.000. Sebuah kapal kontainer membutuhkan 24 hari dan biaya $ 5.000; udara memerlukan waktu 1 hari dan biaya $ 8.000. Holding biaya diperkirakan sebesar 40% dalam kedua kasus. Bagaimana seharusnya pengiriman dilakukan?

Chapter 12, Inventory Management Problem 1: ABC Analysis Stock Number

Annual $ Volume

Percent of Annual $ Volume

J24

12,500

46.2

R26

9,000

33.3

L02

3,200

11.8

M12

1,550

5.8

P33

620

2.3

T72

65

0.2

S67

53

0.2

Q47

32

0.1

V20

30

0.1 = 100.0

What are the appropriate ABC groups of inventory items? Problem 2: A firm has 1,000 “A” items (which it counts every week, i.e., 5 days), 4,000 “B” items (counted every 40 days), and 8,000 “C” items (counted every 100 days). How many items should be counted per day?

Problem 3: Assume you have a product with the following parameters:

Demand = 360 Holding cost per year = $1.00 per unit Order cos t: = $100 per order What is the EOQ?

Problem 4: Given the data from Problem 3, and assuming a 300-day work year; how many orders should be processed per year? What is the expected time between orders?

Problem 5: What is the total cost for the inventory policy used in Problem 3?

Problem 6: Assume that the demand was actually higher than estimated (i.e., 500 units instead of 360 units). What will be the actual annual total cost?

Problem 7: If demand for an item is 3 units per day, and delivery lead-time is 15 days, what should we use for a re-order point? Problem 8: Assume that our firm produces type C fire extinguishers. We make 30,000 of these fire extinguishers per year. Each extinguisher requires one handle (assume a 300 day work year for daily usage rate purposes). Assume an annual carrying cost of $1.50 per handle; production setup cost of $150, and a daily production rate of 300. What is the optimal production order quantity? Problem 9: We need 1,000 electric drills per year. The ordering cost for these is $100 per order and the carrying cost is assumed to be 40% of the per unit cost. In orders of less than 120, drills cost $78; for orders of 120 or more, the cost drops to $50 per unit. Should we take advantage of the quantity discount? Problem 10: Litely Corp sells 1,350 of its special decorator light switch per year, and places orders for 300 of these switches at a time. Assuming no safety stocks, Litely estimates a 50% chance of no shortages in each cycle, and the probability of shortages of 5, 10, and 15 units as 0.2, 0.15, and 0.15 respectively. The carrying cost per unit per year is calculated as $5 and the stockout cost is estimated at $6 ($3 lost profit per switch and another $3 lost in goodwill, or future sales loss). What level of safety stock should Litely use for this product? (Consider safety stock of 0, 5, 10, and 15 units)

Problem 11: Presume that Litely carries a modern white kitchen ceiling lamp that is quite popular. The anticipated demand during lead time can be approximated by a normal curve having a mean of 180 units and a standard deviation of 40 units. What safety stock should Litely carry to achieve a 95% service level?

ANSWERS

Problem 1: ABC Groups Class

Items

Annual Volume

Percent of $ Volume

A

J24, R26

21,500

79.5

B

L02, M12

4,750

17.6

C

P33, T72, S67, Q47, V20

800

2.9 = 100.0

Problem 2: Item Class

Quantity

Policy

Number of Items to Count Per Day

A

1,000

Every 5 days

1000/5 = 200/day

B

4,000

Every days

40 4000/40=100/day

C

8,000

Every days

100 8000/100=80/day

Total items to count: 380/day

Problem 3:

EOQ =

2 * Demand * Order cost 2 * 360 * 100 = = 72000 = 268 items Holding cost 1

Problem 4:

N=

Demand 360 = = 134 . orders per year Q 268

T=

Working days = 300 / 134 . = 224 days between orders Expected number of orders

Problem 5: Demand * Order Cost (Quantity of Items) * (Holding Cost ) 360 * 100 268 * 1 + = + = 134 + 134 = $268 2 Q 268 2

TC =

Problem 6:

TC =

Demand * Order Cost ( Quantity of Items) * ( Holding Cost ) 500 * 100 268 * 1 + = + = 186.57 + 134 = $320.57 Q 2 268 2

Note that while demand was underestimated by nearly 50%, annual cost increases by only 20% (320 / 268 = 1.20) an illustration of the degree to which the EOQ model is relatively insensitive to small errors in estimation of demand.

Problem 7:

ROP = Demand during lead - time = 3 * 15 = 45 units Problem 8:

Q*p =

2 * Demand * Order Cost = Daily Usage Rate Holding Cost 1 − Daily Pr oduction Rate

IJ K

F G H

(2)(30,000)(150) = 3000 units 100 . 1− 150 300

F IJ G H K

Problem 9:

Q*p ($78) =

(2)(1000)(100) = 80 units (0.4)(78)

Q*p ($50) =

(2)(1000)(100) = 100 units = 120 to take advantage of quantity discount. (0.4)(50)

Ordering 100 units at $50 per unit is not possible; the discount does not apply until 120 the order equals 120 units. Therefore, we need to compare the total costs for the two alternatives.

Total cos t = Demand * Cost +

Demand * Order Cost (Quantity of Items) * ( Holding cos t ) + 2 Q

Total cos t ($78) = (1000)( 78) +

(1000)(100) (80)( 0.4)( 78) + = $80,498 80 2

Total cos t ($50) = (1000)(50) +

(1000)(100) (120)(0.4)(50) + = $52,033 120 2

Therefore, we should order 120 each time at a unit cost of $50 and a total cost of $52,033. Problem 10:

Safety stock = 0 units:

Carrying cost equals zero.

Stockout cos ts = (Stockout cos t * possible units of shortage * probability of shortage * number of orders pe

S0 = 6* 5* 0.2 *

1350 1350 1350 + 6 * 10 * 015 . * + 6* 15* 0.15* = $128.25 300 300 300

Safety stock = 5 units: Carrying cos t = $5 per unit * 5 units = $25

Stockout cost: S5 = 6* 5* 0.15*

1350 1350 + 6 * 10 * 015 . * = $60.75 300 300

Total cos t = carrying cos t + stockout cos t = $25 + $60.75 = $85.75

Safety stock = 10 units: Carrying cos t = 10 * 5 = $50.00

Stockout cost: S10 = 6 * 5* 015 . *

1350 = $20.25 300

Total cos t = carrying cos t + plus stockout cos t = $50.00 + $20.25 = $70.25

Safety stock = 15: Carrying cos t = 15* 5 = $75.00 Stockout cos ts = 0 (there is no shortage if 15 units are maintained)

Total cos t = carrying cos t + stockout cos t = $75.00 + $0 = $75.00 Therefore: Minimum cost comes from carrying a 10-unit safety stock. Problem 11: To find the safety stock for a 95% service level it is necessary to calculate the 95th percentile on the normal curve. Using the standard Normal table from the text, we find the Z value for 0.95 is 1.65 standard units. The safety stock is then given by:

(165 . * 40) + 180 = 66 + 180 = 246 Ceiling Lamps

Praktek Masalah: Bab 12, Manajemen Persediaan Masalah 1: Analisis ABC Jumlah Saham Tahunan $ Volume Persen Tahunan $ Volume J24 12.500 46,2 R26 9.000 33,3 L02 3.200 11,8 M12 1.550 5.8 P33 620 2.3 T72 65 0.2 53 S67 0.2 Q47 32 0.1 30 V20 0,1 100,0 =Σ Apa ABC sesuai kelompok barang inventaris?

Masalah 2: perusahaan A memiliki 1.000 "A" item (yang penting setiap minggu, yaitu 5 hari), 4.000 "B" item (dihitung setiap 40 hari), dan 8.000 "C" item (dihitung setiap 100 hari). Berapa banyak item yang harus dihitung per hari? Masalah 3: Asumsikan Anda memiliki produk dengan parameter berikut: Holding biaya per per unit Order per pesanan Apa EOQ itu? Masalah 4: Mengingat data dari Soal 3, dan dengan asumsi setahun 300 hari kerja; berapa banyak pesanan harus diproses per tahun? Apakah waktu yang diharapkan antara pesanan? Masalah 5: Berapa biaya total untuk kebijakan persediaan yang digunakan pada Soal 3? Masalah 6: Asumsikan bahwa permintaan itu sebenarnya lebih tinggi dari perkiraan (misalnya, 500 unit bukan 360 unit). Apa yang akan menjadi biaya total aktual tahunan? Masalah 7: Jika permintaan untuk item adalah 3 unit per hari, dan pengiriman lead-waktu 15 hari, apa yang harus kita gunakan untuk titik re-order? Masalah 8: Asumsikan bahwa perusahaan kami memproduksi alat pemadam kebakaran tipe C. Kami membuat 30.000 dari pemadam kebakaran per tahun. Setiap pemadam memerlukan satu handle (menganggap 300 hari kerja tahun berjalan tingkat penggunaan harian). Asumsikan biaya tercatat tahunan sebesar $ 1,50 per menangani; produksi setup biaya sebesar $ 150, dan tingkat produksi harian 300. Apakah jumlah produksi yang optimal memesan?

Soal 9: Kita perlu latihan listrik 1.000 per tahun. Biaya pemesanan untuk ini adalah $ 100 per order dan biaya tercatat diasumsikan 40% dari biaya per unit. Dalam pesanan kurang dari 120, bor biaya $ 78, untuk pesanan 120 atau lebih, biaya turun menjadi $ 50 per unit. Haruskah kita mengambil keuntungan dari diskon kuantitas? Masalah 10: Litely Corp menjual 1.350 dari dekorator khusus beralih pada lampu per tahun, dan tempattempat pesanan untuk 300 switch ini pada suatu waktu. Dengan asumsi tidak ada saham keselamatan, Litely memperkirakan 50% kemungkinan tidak ada kekurangan dalam setiap siklus, dan probabilitas kekurangan 5, 10, dan 15 unit sebagai 0,2, 0,15, dan 0,15 masingmasing. Biaya perolehan per unit per tahun dihitung sebagai $ 5 dan biaya stockout diperkirakan $ 6 ($ 3 keuntungan hilang per saklar dan lain $ 3 hilang dalam goodwill, atau masa depan rugi penjualan). Apa tingkat safety stock Litely harus digunakan untuk produk ini? (Pertimbangkan safety stock dari 0, 5, 10, dan 15 unit)

Masalah 11: Menganggap bahwa Litely membawa lampu langit-langit dapur modern putih yang cukup populer. Mengantisipasi permintaan selama lead time dapat didekati dengan kurva normal yang memiliki rata-rata 180 unit dan deviasi standar 40 unit. Apa safety stock Litely harus membawa untuk mencapai tingkat pelayanan 95%?

Chapter 13, Aggregate Planning Problem 1: Set the following problem up in transportation format and solve for the minimum cost plan.

Period Feb

Mar

Apr

55

70

75

Regular

50

50

50

Overtime

5

5

5

Subcontract

12

12

10

Beginning Inventory

10

Demand

Capacity

Costs Regular time

$60 per unit

Overtime

$80 per unit

Subcontract

$90 per unit

Inventory carrying cost

$1 per unit per month

Back order cost

$3 per unit per month

ANSWERS

Problem 1:

Soal Praktek: Bab 13, Perencanaan Agregat Masalah 1: Mengatur masalah berikut dalam format transportasi dan memecahkan untuk rencana biaya minimum. Periode Feb Mar Apr Permintaan 55 70 75 Kapasitas Reguler 50 50 50 Lembur 5 5 5 Subkontrak 12 12 10 Awal Persediaan 10

Biaya Regular waktu $ 60 per unit Lembur $ 80 per unit Subkontrak $ 90 per unit Membawa persediaan biaya $ 1 per unit per bulan Kembali rangka biaya $ 3 per unit per bulan

Chapter 14, Material Requirements Planning (MRP) and ERP Problem 1: The Hunicut and Hallock Corporation makes two versions of the same basic file cabinet, the TOL (Top-of-the-line) five drawer file cabinet and the HQ (High-quality) five drawer filing cabinet.

The TOL and HQ use the same cabinet frame and locking mechanism. The drawer assemblies are different although both use the same drawer frame assembly. The drawer assemblies for the TOL cabinet use a sliding assembly that requires four bearings per side whereas the HQ sliding assembly requires only two bearings per side. (These bearings are identical for both cabinet types.) 100 TOL and 300 HQ file cabinets need to be assembled in week #10. No current stock exists.

Develop a material structure tree for the TOL and the HQ file cabinets.

Problem 2: Develop a gross material requirements plan for the TOL and HQ cabinets in the previous example.

Problem 3: Develop a net material requirements plan for the TOL and HQ file cabinets in the previous problems assuming a current on-hand finished goods inventory of 100 TOL cabinets. The lead times are given below. Painting and final assembly of both HQ and TOL requires 2 weeks.

Both cabinet frames and lock assembly require 1 week for manufacturing. Both drawer assemblies require 2 weeks for assembly. Both sliding assemblies require 2 weeks for manufacturing. Bearings require 2 week to arrive from the supplier.

Problem 4: If the TOL file cabinet has a gross material requirements plan as shown below, no inventory, and 2 weeks lead time is required for assembly, what are the order release dates and lot sizes when lot sizing is determined using lot-for-lot? Use a holding cost of $2.00 and a setup cost of $20.00, and assume no initial inventory. Gross Material Requirements Plan Week

1

2

3

TOL

4

50

5

6

100

7

8

9

50

10 100

Problem 5: If the TOL file cabinet has a gross material requirements plan as shown below, no inventory, and 2 weeks of lead time is required for assembly, what are the order release dates and lot sizes when lot sizing is determined by EOQ (Economic Order Quantity)? Use a holding cost of $2.00 and a setup cost of $20.00, and assume no initial inventory. Gross Material Requirements Plan Week

1

2

3

TOL

4

50

5

6

100

7

8

9

10

50

100

Problem 6: If the TOL file cabinet has a gross materials requirements plan as shown below, no inventory, and 2 weeks of lead time is required for assembly, what are the order release dates and lot size when lot sizing is determined using PPB (part period balancing)? Use a holding cost of $2.00 and a setup cost of $20,000, and no initial inventory.

Gross Material Requirements Plan Week TOL

1

2

3 50

4

5 100

6

7 50

8

9

10 100

ANSWERS

Problem 1:

Problem 2:

Gross Requirements Plan Week

1

2

3

4

5

6

7

8

9

10

TOL

100

HQ

300

Problem 3:

Week

1

Required date TOL Order release date

2

3

4

5

6

7

8

9

10

Lead Time

100

2 weeks

Required date

300

2 weeks

HQ

Cabinet frame and lock

HQ drawer assembly

Drawer frame assembly

HQ sliding assembly

Order release date

30 0

Required date

30 0

1 week

15 00

2 weeks

Order release date

30 0

Required date Order release date

15 00

Required date

15 00

2 weeks

15 00

2 weeks

Order release date

15 00

Required date Order release date

15 00

Required date

60 00

Bearings Order release date

60 00

Receipts: 300 cabinet frames and locks in week 8 1500 HQ drawer assemblies in week 8

2 weeks

1500 drawer frame assemblies in week 6 1500 HQ sliding assemblies in week 6 6000 bearings in week 4

Problem 4:

Gross Material Requirements Plan Week

1

2

TOL Release dates and lot sizes

50

3

4

5

50

100

100

50

6

7

8

9

50

10 100

100

Holding cost = $0 Setup cost = 4 * $20 = $80 Total cost = $80

Problem 5:

Solution using POM for Windows: Gross Material Requirements Plan Week

1

TOL Release dates and lot sizes

72

2

3

4

5

50

100

96

48

6

7

8

50

9

10 100

96

Holding cost = $280 Setup cost = 4 * $20 = $80 Total cost = $360

Bab 14, Material Requirements Planning (MRP) dan ERP Masalah 1: Para Hunicut dan Hallock Corporation membuat dua versi dari lemari file yang sama dasar, TOL (Top-of-the-line) lima lemari laci file dan HQ (High-kualitas) lima laci lemari arsip.

Para TOL dan HQ menggunakan frame kabinet yang sama dan mekanisme penguncian. Majelis laci berbeda meskipun keduanya menggunakan perakitan laci yang sama frame. majelis Laci untuk kabinet TOL menggunakan perakitan geser yang memerlukan empat bantalan per sisi sedangkan perakitan HQ geser membutuhkan hanya dua bantalan tiap sisi. (Ini bantalan yang identik untuk kedua jenis kabinet.) 100 TOL dan 300 HQ lemari arsip harus dirakit pada minggu # 10. Tidak ada saham saat ini ada. Mengembangkan pohon bahan struktur untuk TOL dan lemari arsip kantor pusat. Masalah 2: Mengembangkan bahan rencana kebutuhan kotor untuk lemari TOL dan HQ pada contoh sebelumnya. Masalah 3: Mengembangkan bahan rencana kebutuhan bersih untuk TOL dan lemari arsip HQ dalam masalah sebelumnya dengan asumsi pada saat tangan persediaan barang jadi dari 100 lemari TOL. Memimpin kali diberikan di bawah ini. perakitan Lukisan dan akhir dari kedua HQ dan TOL membutuhkan 2 minggu. frame kabinet Baik dan perakitan kunci memerlukan 1 minggu untuk pembuatan. Kedua majelis laci memerlukan 2 minggu untuk perakitan. Kedua majelis geser memerlukan 2 minggu untuk pembuatan. Bearings memerlukan 2 minggu untuk datang dari pemasok. Masalah 4: Jika lemari arsip TOL memiliki rencana kebutuhan material kasar seperti yang ditunjukkan di bawah ini, tidak ada persediaan, dan 2 minggu lead time dibutuhkan untuk perakitan, apa tanggal rilis order dan ukuran banyak saat lot sizing ditentukan dengan-banyak-banyak untuk? Gunakan biaya penyimpanan sebesar $ 2,00 dan biaya setup sebesar $ 20.00, dan menganggap tidak memiliki persediaan awal. Persyaratan Bahan Rencana Bruto Minggu 1 2 3 4 5 6 7 8 9 10 TOL 50 100 50 100 Masalah 5: Jika lemari arsip TOL memiliki rencana kebutuhan material kasar seperti yang ditunjukkan di bawah ini, tidak ada persediaan, dan 2 minggu lead time dibutuhkan untuk perakitan, apa tanggal rilis order dan ukuran banyak saat lot sizing ditentukan oleh EOQ (Economic Order Quantity) ? Gunakan biaya penyimpanan sebesar $ 2,00 dan biaya setup sebesar $ 20.00, dan menganggap tidak memiliki persediaan awal. Persyaratan Bahan Rencana Bruto Minggu 1 2 3 4 5 6 7 8 9 10 TOL 50 100 50 100

Masalah 6: Jika lemari arsip TOL memiliki bahan-bahan kotor persyaratan rencana seperti yang ditunjukkan di bawah ini, tidak ada persediaan, dan 2 minggu lead time dibutuhkan untuk perakitan, apa tanggal rilis pesanan dan ukuran banyak saat lot sizing ditentukan dengan PPB (menyeimbangkan bagian periode) ? Gunakan biaya penyimpanan sebesar $ 2,00 dan biaya setup sebesar $ 20.000, dan tidak ada persediaan awal. Persyaratan Bahan Rencana Bruto Minggu 1 2 3 4 5 6 7 8 9 10 TOL 50 100 50 100

Chapter 15, Short Term Scheduling Problem 1: Assume that Susan is a sorority pledge coordinator with four jobs and only three pledges. The table below gives the expected time for each pledge to do each job. Job 1

Job 2

Job 3

Job 4

4

9

3

8

Barbara 7

8

2

6

Jennifer 3

4

5

7

Alice

If she wishes to minimize the time taken, to whom should she assign which job? Problem 2: Five jobs are to be done at custom furniture shop: Job Days Date to Promised Finish (in Days from Today) A

2

5

B

8

8

C

6

12

D

4

10

E

1

4

Compare the effect of the scheduling methods (A) FCFS (first come, first served), (B) EDD (earliest due date), and (C) SPT (smallest processing time).

Problem 3: The following six jobs are waiting to be processed: Job

Hours Time to Due Process

#407 2

7

#281 8

16

#306 4

4

#429 10

17

#038 5

15

#998 12

18

Develop the appropriate sequencing for these jobs using the Critical Ratio criteria. Problem 4: Five jobs go through two work centers, as shown below: Job

Hours Required Varnishing Painting (Center 1) (Center 2)

R

4

5

S

17

7

T

14

12

U

9

2

V

11

6

What is the appropriate sequence for these jobs?

ANSWERS

Problem 1: First, begin with the following assignment table:

Job 1

Job 2

Job 3

Job 4

4

9

3

8

Barbara 7

8

2

6

Jennifer 3

4

5

7

Dummy 0

0

0

0

Alice

Note: The “dummy” must be added because we have four jobs and only three people. Solve this table for the set of assignments giving the minimum total job time. Your final table should look like:

Job 1

Job 2

Job 3

Job 4

0

4

0

3

Barbara 4

4

0

2

Jennifer 0

0

3

3

Dummy 1

0

2

0

Alice

The set of optimal assignments would then be: Alice - Job 1 Barbara - Job 3 Jennifer - Job 2

Dummy - Job 4 Note that Job 4 does not get done since it is assigned to the “Dummy.” Problem 2: (A) FCFS Sequence

Process Flow Due Lateness Time Time Date

A

2

2

5

0

B

8

10

8

2

C

6

16

12

4

D

4

20

10

10

E

1

21

4

17

TOTALS 21

69

33

Average completion time = 69 / 5 = 13.8 days Average number of jobs in the system = 69 / 21 = 3.28 jobs Average lateness = 33 / 5 = 6.6 days

Utilization = 21 / 69 = 30.4% (B) EDD Sequence

Process Flow Due Lateness Time Time Date

E

1

1

4

0

A

2

3

5

0

B

8

11

8

3

D

4

15

10

5

C

6

21

TOTALS 21

12

51

9 17

Utilization = 21 / 51 = 41.2% (C) SPT Sequence Process Flow Due Lateness Time Time Date E

1

1

4

0

A

2

3

5

0

D

4

7

10

0

C

6

13

12

1

B

8

21

8

13

TOTALS 21

45

14

Average completion time = 45 / 5 = 9 days Average number of jobs in the system = 45 / 21 = 2.14 jobs Average lateness = 14 / 5 = 2.8 days

Utilization = 21 / 45 = 46.7% Problem 3: Job

Hours to Time Process Due

Computed Critical Ratio

#407

2

7

7/2 = 3.5

#281

8

16

16/8 = 2.0

#306

4

4

4/4 = 1.0

#429

10

17

17/10 = 1.7

#038

5

15

15/5 = 3.0

#998

12

18

18/12 = 1.5

Critical Critical Ratio Ratio Sequence #306

1.0

#998

1.5

#429

1.7

#281

2.0

#038

3.0

#407

3.5

Problem 4:

Soal Praktek: Bab 15, Penjadwalan Jangka Pendek Masalah 1: Asumsikan bahwa Susan adalah janji mahasiswi koordinator dengan empat pekerjaan dan hanya tiga janji. Tabel di bawah ini memberikan waktu yang diharapkan untuk setiap janji untuk melakukan pekerjaan masing-masing. Ayub 1 Job 2 Job 3 Job 4 Alice 4 9 3 8

Barbara 7 8 2 6 Jennifer 3 4 5 7

Jika dia ingin meminimalkan waktu yang dibutuhkan, kepada siapa ia harus menetapkan yang pekerjaan?

Masalah 2: Lima pekerjaan harus dilakukan di toko furnitur kustom: Hari Ayub Dijanjikan Selesai Tanggal (Dalam hari dari Today) A25 B88 C 6 12 D 4 10 E14 Bandingkan pengaruh metode penjadwalan (A) FCFS (first come, first served), (B) EDD (jatuh tempo awal), dan (C) SPT (waktu proses terkecil).

Masalah 3: Keenam berikut pekerjaan sedang menunggu untuk diproses: Jam Ayub Proses Sisa Karena # 407 2 7 # 281 8 16 # 306 4 4 # 429 10 17 # 038 5 15 # 998 12 18 Mengembangkan urutan yang sesuai untuk pekerjaan ini menggunakan kriteria Rasio Kritis.

Masalah 4: Lima pekerjaan melalui dua pusat bekerja, seperti yang ditunjukkan di bawah ini: Jam Kerja Diperlukan Varnishing (Pusat 1) Lukisan (Center 2) R45 S 17 7 T 14 12 U92 V 11 6 Apa urutan tepat untuk pekerjaan ini?

Chapter 16, Just-in-Time Systems Problem 1: Bryant Electronics produces short runs of battery-powered pocket lanterns. You have been asked to reduce inventory by introducing a kanban system. After several hours of analysis you have developed the following data for connectors used in one work cell. How many kanbans do you need for this connector? Daily demand 1,500 units Production lead-time 1 day Safety stock 1 day Kanban size 250 units

Problem 2: Perkins Lighting wishes to employ a kanban in their new floor lamp production system. For the floor lamp base, they have provided the following information: Daily demand 300 units Holding cost $20/unit/year Order cost $10/order Lead time 2 days Safety stock 600 units Find the size of the kanban and the number of kanbans required.

ANSWERS

Problem 1:

Demand during lead time = 1,500 Safety stock = 1,500 Therefore: Maximum inventory level = 1,500 + 1,500 = 3, 000 Number of kanbans needed = maximum inventory level/kanban size = 3000 / 250 = 12

Problem 2: Daily demand 300 units Holding cost $20/unit/year Order cost $10/order Lead time 2 days Safety stock 2 days demand Find the size of the kanban and the number of kanbans required. Assume that the size of the kanban is the EOQ:

Q=

2 * Demand * Order cost Holding cost

=

2 *300 * 300 *10 20

= 90, 000 = 300 units

∴ kanban size = 300

Number of kanbans = (demand during lead time + safety stock) / size of kanban = [(2 * 300) + 600] / 300 = 1200 / 300 = 4 kanbans

Soal Praktek: Bab 16, Just-in-Time Systems Masalah 1: Elektronik Bryant menghasilkan berjalan singkat lentera saku bertenaga baterai. Anda telah diminta untuk mengurangi persediaan dengan memperkenalkan sistem kanban. Setelah beberapa jam analisis Anda telah mengembangkan data berikut untuk konektor yang digunakan dalam satu sel kerja. Berapa banyak kanbans yang anda butuhkan untuk konektor ini? Harian permintaan 1.500 unit Produksi lead-time 1 hari Safety stock 1 hari Kanban ukuran 250 unit Masalah 2: Perkins Lighting ingin mempekerjakan kanban di lantai baru sistem mereka produksi lampu. Untuk lampu lantai dasar, mereka telah memberikan informasi berikut: Harian permintaan 300 unit Holding biaya $ 20/unit/year Order biaya $ 10/order Lead waktu 2 hari Safety stock 600 unit Cari ukuran kanban dan jumlah kanbans diperlukan.

Chapter 17, Maintenance and Reliability Problem 1: California Instruments, Inc., produces 3,000 computer chips per day. Three hundred are tested for a period of 500 operating hours each. During the test, six failed: two after 50 hours, two at 100 hours, one at 300 hours, and one at 400 hours.

Find FR(%) and FR(N). Problem 2: If 300 of these chips are used in building a mainframe computer, how many failures of the computer can be expected per month? Problem 3: Find the reliability of this system:

Problem 4: Given the probabilities below, calculate the expected breakdown cost.

Number of Breakdowns

Daily Frequency

0

3

1

2

2

2

3

3

Assume a cost of $10 per breakdown.

ANSWERS

Problem 1: FR(%) = failures per number tested = 6/300 = 0.02 = 2% FR(N) = failures per operating time: Total time = 300 * 500 = 150,000 hours Downtime = 2(450) + 2(400) + 1(200) + 1(100) = 2,000 hours Operating time = Total time – Downtime = 150,000 – 2,000 = 148,000 Therefore: FR(N) = 6/148,000 = 0.0000405 failures/hour MTBF = 1/FR(N) = 24,691 hours

Problem 2: Converting the units of FR(N) to months: FR(N) = 0.0000405 * 24 hours/day * 30 days/month = 0.029 failures/month FR(N) for the 300 units: FR(N) = 0.029 failures/month * 300 units = 8.75 failures/month MTBF for the mainframe: MTBF = 1/FR(N) = 1/8.75 = 0.11 month = 0.11 * 30 = 3.4 days

Calculation for MTBF assumes that failure of any one chip brings down entire system. Problem 3:

R = [0.95 + 0.92(1 − 0.95)] * [0.98] * [0.90 + 0.90(1 − 0.90)]

= 0.996 * 0.98 * 0.99 = 96.6% Problem 4:

Number of Breakdowns

Daily Frequency

Probability

0 1

3 2

0.3 0.2

2

2

0.2

3

3

0.3

Expected number of breakdowns = (0)(0.3) + (1)(0.2) + (2)(0.2) + (3)(0.3) = 0 + 0.2 + 0.4 + 0.9 = 1.5 breakdowns/day Expected breakdown cost = Expected number of breakdowns * Cost per breakdown = 1.5 * $10 = $15/day

Praktek Masalah: Bab 17, Pemeliharaan dan Keandalan Masalah 1: California Instruments, Inc, memproduksi chip komputer 3.000 per hari. Tiga ratus diuji untuk jangka waktu 500 jam operasi masing-masing. Selama pengujian, enam gagal: dua setelah 50 jam, dua jam 100 jam, satu jam 300 jam, dan satu di 400 jam. Cari FR (%) dan FR (N). Masalah 2: Jika 300 chip ini digunakan dalam membangun sebuah komputer mainframe, berapa banyak kegagalan komputer dapat diharapkan per bulan? Masalah 3:

Temukan keandalan sistem ini:

Masalah 4: Mengingat probabilitas bawah, menghitung biaya kerusakan yang diharapkan. Jumlah kerusakan Frekuensi Harian 03 12 22 33 Asumsikan biaya sebesar $ 10 per breakdown.

Practice Problems: Module A, Decision Making Problem 1: Bascomb’s Candy is considering the introduction of a new line of products. In order to produce the new line, the bakery is considering either a major or minor renovation of the current plant. The market for the new line of products could be either favorable or unfavorable. Bascomb’s Candy has the option of not developing the new product line at all. Develop the appropriate decision tree.

Problem 2: With major renovation, at Bascomb’s Candy (See Problem 1 above) the payoff from a favorable market is $100,000, from an unfavorable market $ − 90,000 . Minor renovations and favorable market has a payoff of $40,000 and an unfavorable market $ − 20,000 . Assuming that a favorable market and an unfavorable market are equally likely, solve the decision tree. Problem 3: Jeff Heyl, the owner of Bascomb’s Candy (Problem 1 and 2 above) realizes that he should get more information before making his final decision. He decides to contract with a market research firm to conduct a market survey. How much should Jeff be willing to pay for accurate information (i.e. What is the Expected Value of Perfect Information, EVPI?)?

ANSWERS

Problem 1:

Problem 2:

Therefore, the appropriate choice under equally likely market conditions is to make the minor modifications ( EMV = $10,000.)

Problem 3: With knowledge of when a favorable market will occur, Jeff’s best payoff is major renovation. This happens 1 2 the time. $100,000 * .5 = $50,000

When unfavorable market exists, Jeff will do nothing, which happens

1

2

the time.

0 * .5 = $0.0 so Perfect Information yields = ($100,000 * .5) + ( 0 * .5) = $50,000

Therefore EMV is $10,000 vs. $50,000 with Perfect Information and EVPI = $50,000 − $10,000 = $40,000

Practice Problems: Module B, Linear Programming Problem 1: Chad’s Pottery Barn has enough clay to make 24 small vases or 6 large vases. He has only enough of a special glazing compound to glaze 16 of the small vases or 8 of the large vases. Let X1 = the number of small vases and X2 = the number of large vases. The smaller vases sell for $3 each, and the larger vases would bring $9 each.

(a) Formulate the problem (b) Solve the problem graphically Problem 2: A fabric firm has received an order for cloth specified to contain at least 45 pounds of cotton and 25 pounds of silk. The cloth can be woven out of any suitable mix of two yarns A and B. They contain the proportions of cotton and silk (by weight) as shown in the following table:

Cotton

Silk

A

30%

50%

B

60%

10%

Material A costs $3 per pound, and B costs $2 per pound. What quantities (pounds) of A and B yarns should be used to minimize the cost of this order?

ANSWERS

Problem 1: (a) Formulation: Objective function:

Maximize

3X1 + 9X2

Clay constraint:

1X1 + 4X2 ≤ 24

Glaze constraint:

1X1 + 2X2 ≤ 16

Subject to:

(b) Graphical Solution

X1 @ $3.00

X2 @ $9.00

Income

A

0

0

0

B

0

6

$54

C

8

4

$60*

D

16

0

$48

Evaluating all possible corner points that might be the optimal solution, the optimum income of $60 will occur by making and selling 8 small vases and 4 large vases. An iso-profit line on the graph from (20,0) to (0,6.67) shows the point that returns value of $60. Problem 2: Formulation: Objective function:

min C =

3A +

2B

Constraints:

Cotton

.30A + .60B ≥ 45

Silk

.50A + .10B ≥ 25

We can learn the values of A and B at intersection of the Silk and Cotton constraints by simultaneously solving the equations that determine the point. To solve for A we first multiply the Silk equation by 6 then subtract the Cotton equation.

3.0 A + .60 B = 150 (Silk constraint multiplied by 6) .30 A + .60 B = 45 (subtract Cotton equation) 2.70 A = 105 A = 38.8

Following the same basic procedure for the value of B, we multiply the Cotton equation by 3 and the Silk equation by 5 and subtract the Silk equation.

1.50 A + 3.0 B = 225 (Cotton equation multiplied by 5) 1.50 A + .30 B = 75 (Silk equation multiplied by 3 and subtracted) 2.70 B = 150 B = 55.6 Using the Objective Function, we can calculate the profit at each of the three corner points: Axis intercept (0, 250) = (0 * $3) + (250 * $2) = $500 Axis intercept (150, 0) = (150 * $3) + 0 * $2) = $350 Intersection of the two constraints (38.8, 55.5) = (38.8 * $3) + (55.6 * $2) = $227.60 The minimum cost is found at the intersection of the two constraint equations. Praktek Masalah: Modul B, Linear Programming Masalah 1: Chad Pottery Barn memiliki cukup tanah liat untuk membuat 24 vas kecil atau 6 vas besar. Dia hanya cukup dari senyawa kaca khusus untuk Glaze 16 dari vas kecil atau 8 dari vas besar. Biarkan X1 = jumlah vas kecil dan X2 = jumlah vas besar. Vas kecil menjual sebesar $ 3 masing-masing, dan vas yang lebih besar akan membawa $ 9 masing-masing. (A) Merumuskan masalah (B) Memecahkan masalah grafis Masalah 2: Sebuah perusahaan kain telah menerima pesanan untuk kain ditentukan untuk mengandung paling sedikit 45 pon kapas dan 25 pon sutra. kain tenun ini dapat keluar dari setiap campuran yang cocok dari dua benang A dan B. Mereka mengandung proporsi kapas dan sutra (dengan berat) seperti terlihat dalam tabel berikut: Cotton Silk A% 30 50% B 60% 10% Bahan A biaya $ 3 per pon, dan biaya B $ 2 per pon. Apa jumlah (pon) A dan B benang harus

digunakan untuk meminimalkan biaya pesanan ini?

Practice Problems: Module C, Transportation Models Problem 1: John Galt Shipping wishes to ship a product that is made at two different factories to three different warehouses. They produce 18 units at Factory A and 22 units at Factory B. They need 10 units in warehouse #1, 20 units in warehouse #2, and 10 units in warehouse #3. Per unit transportation costs are shown in the table below. How many units should be shipped from each factory to each warehouse? Warehouse #1

Warehouse #2

Warehouse #3

Plant A

$4

$2

$3

Plant B

$3

$2

$1

Problem 2: Assume that in Problem 1 the demand at each warehouse is increased by 4 units. Now how many units should be shipped from each factory to each warehouse?

ANSWERS

Problem 1:

Problem 2:

Note that we had to use a “Dummy Factory” to supply the extra products as demand exceeds the quantity available from just the two factories. Praktek Masalah: C Modul, Model Transportasi

Masalah 1: John Galt Pengiriman ingin kapal produk yang dibuat di dua pabrik yang berbeda untuk tiga gudang yang berbeda. Mereka menghasilkan 18 unit di Pabrik unit A dan 22 di Pabrik B. Mereka perlu 10 unit di gudang # 1, 20 unit di gudang # 2, dan 10 unit di gudang # 3. Per unit biaya transportasi ditunjukkan dalam tabel di bawah ini. Berapa jumlah yang harus dikirim dari setiap pabrik ke gudang masing-masing? # 1 Gudang Gudang Gudang # 2 # 3 Tanaman A $ 4 $ 2 $ 3 Pabrik B $ 3 $ 2 $ 1

Masalah 2: Asumsikan bahwa pada Soal 1 permintaan di gudang masing-masing meningkat sebesar 4 unit. Sekarang berapa jumlah yang harus dikirim dari setiap pabrik ke gudang masing-masing?

Practice Problems: Module D, Waiting-Line Models Problem 1: A new shopping mall is considering setting up an information desk manned by one employee. Based upon information obtained from similar information desks, it is believed that people will arrive at the desk at a rate of 20 per hour. It takes an average of 2 minutes to answer a question. It is assumed that the arrivals follow a Poisson distribution and answer times are exponentially distributed. (a) Find the probability that the employee is idle. (b) Find the proportion of the time that the employee is busy. (c) Find the average number of people receiving and waiting to receive some information. (d) Find the average number of people waiting in line to get some information. (e) Find the average time a person seeking information spends in the system. (f) Find the expected time a person spends just waiting in line to have a question answered (time in the queue). Problem 2:

Assume that the information desk employee in Problem 1 earns $10 per hour. The cost of waiting time, in terms of customer unhappiness with the mall, is $12 per hour of time spent waiting in line. Find the total expected costs over an 8-hour day. Problem 3: The shopping mall has decided to investigate the use of two employees on the information desk. (a) Find the probability of no people in the system. (b) Find the average number of people waiting in this system. (c) Find the expected time a person spends waiting in this system. (d) Assuming the same salary level and waiting costs as in Problem 2, find the total expected costs over an 8-hour day.

Problem 4: Three students arrive per minute at a coffee machine that dispenses exactly four cups per minute at a constant rate. Describe the system parameters. Problem 5: A repairman at a local metal working shop services their five drill presses. Service time averages 10 minutes and is exponentially distributed. Machines breakdown after an average of 70 minutes operation (following a Poisson distribution). Describe the major system characteristics.

ANSWERS

Problem 1:

(a) P0 = 1 −

(b) p =

λ 20 = 1− = 0.33 => 33% µ 30

λ = 0.66 µ

(c) Ls =

λ 20 = = 2 people λ − µ 30 − 20

(d) Lq =

λ2 202 = = 1.33 people µ (µ − λ ) 30(30 − 20)

(e) Ws =

1 1 = = 0.10 hours λ − µ 30 − 20

(f) Wq =

λ 20 = = 0.0667 hours µ ( µ − λ ) 30(30 − 20)

Problem 2: From the solution to Problem 1: The average person waits 0.0667 hours and there are 160(20 arrivals * 8 hours) arrivals per day. Therefore: Total waiting time = 160 x 0.0667 = 10.67 hours Total cost for waiting = Total waiting time * Cost per hour = 10.67 * $12 = $128 per day. Salary cost = 8 hours * $10 = $80 Total cost = Salary cost + Waiting cost = $80 + $128 = $208 per day.

Problem 3:

λ = 20 per hour µ = 30 per hour M = 2 open channels (servers) (a)

P0 =

1 1  20  1  20  1  20   2(30)    +   +   0!  30  1!  30  2  30   2(30) − 20  0

1

=

1 2 1  4   60  1+ +     3 2  9   60 − 20 

=

1 1 = = 50% 2 1 2 1+ + 3 3

2

(b) 2   20    (20)(30)     30    1  + 20 Ls =   (1)[(2)(30) − 20]2   2  30    

  800    3  1 2  + =   1600  2 3   =

1 8 + = 0.75 people 12 12

(c)

Ws =

Ls 0.75 = = 0.0375 hours λ 20

Problem 4:

Lq =

λ2 = 1.125 people in the queue on average 2µ ( µ − λ )

Wq =

λ = 0.375 minutes in the queue waiting 2 µ (µ − λ )

Ls = Lq +

λ = 1.87 people in the system µ

Ws = Wq +

1 = 0.625 minutes in the system µ

Problem 5: N=5 T = 10 minutes U = 70 minutes M = 1 server

X =

T 10 = = 0.125 T + U 10 + 70

From Table D.8: where X = .125 and number of service channels = 1, D = 0.473, F = 0.920 Average number waiting = L = N(1 – F) = 5(1 – 0.920) = 0.4 Average number of machines running = J = NF(1 – X) = 5(0.920)(1 – 0.125) = 4.025 machines Average number of machines being serviced = H = FNX = (0.920)(5)(0.125) = 0.575 machines Probability of no wait = 1 – D = 1 – 0.473 = 0.527

Praktek Masalah: Modul D, Menunggu-Line Model Masalah 1: Sebuah pusat perbelanjaan baru sedang mempertimbangkan mendirikan sebuah meja informasi yang dijaga oleh seorang karyawan. Berdasarkan informasi yang diperoleh dari meja informasi yang sama, diyakini bahwa orang akan tiba di meja di tingkat 20 per jam. Dibutuhkan rata-rata 2 menit untuk menjawab pertanyaan. Diasumsikan bahwa kedatangan mengikuti distribusi Poisson kali dan jawaban yang eksponensial didistribusikan. (A) Carilah probabilitas bahwa karyawan idle. (B) Carilah proporsi waktu yang karyawan sibuk. (C) Tentukan jumlah rata-rata orang yang menerima dan menunggu untuk menerima beberapa informasi. (D) Tentukan jumlah rata-rata orang yang menunggu dalam antrean untuk mendapatkan beberapa informasi. (E) Cari waktu rata-rata orang yang mencari informasi menghabiskan dalam sistem. (F) Cari waktu yang diharapkan seseorang menghabiskan hanya menunggu sesuai untuk menjawab pertanyaan (waktu dalam antrian).

Masalah 2: Asumsikan bahwa meja informasi karyawan pada Soal 1 mendapatkan $ 10 per jam. Biaya waktu tunggu, dalam hal ketidakbahagiaan pelanggan dengan mall, adalah $ 12 per jam dari waktu yang dihabiskan menunggu di garis. Cari diharapkan biaya total selama sehari 8 jam. Masalah 3: Pusat perbelanjaan telah memutuskan untuk menyelidiki penggunaan dua karyawan di meja informasi. (A) Carilah probabilitas tidak ada orang di sistem. (B) Tentukan jumlah rata-rata orang yang menunggu dalam sistem ini. (C) Carilah waktu yang diharapkan seseorang menghabiskan menunggu dalam sistem ini. (D) Dengan asumsi tingkat gaji yang sama dan menunggu biaya seperti di Soal 2, menemukan Prakiraan biaya total selama sehari 8 jam.

Masalah 4: Tiga siswa tiba per menit pada mesin kopi yang membagi-bagikan tepat empat cangkir per menit dengan laju yang konstan. Jelaskan parameter sistem. Masalah 5: Sebuah reparasi di metal lokal yang bekerja jasa toko lima mereka menekan bor. Waktu pelayanan rata-rata 10 menit dan didistribusikan secara eksponensial. Mesin rusak setelah operasi rata-rata 70 menit (jika suatu distribusi Poisson). Menggambarkan karakteristik sistem utama.

Practice Problems: Module E, Learning Curves Problem 1: The initial external tank for NASA’s Space Shuttle took 400 hours of labor to produce. The learning rate is 80%. How long will the twentieth tank take?

Problem 2: An operation has a 90% learning curve and the first unit produced took 28 minutes. The labor cost is $20 per hour.

(a) How long will the second unit take? (b) How much should the second unit cost? Problem 3: Using the data from Problem 1, how long will it take to produce all 20 tanks?

ANSWERS

Problem 1: From Table E.3 where N = 20 and an 80% learning rate: Learning curve coefficient C = .381 Y20 = Y1C = .381 * 400 = 152.4 hours Problem 2: (a) TN + T2C = 28 * 0.9 = 25.2 minutes (b) Cost = (25.2 minutes/60 minutes) ($20 per hour) = $8.40

Problem 3: From Table E.3 where N = 20 and an 80% learning rate: Total time = 10.485

TN = T1C = 400hr * 10.485 = 4,194 hours Masalah Praktek: E Modul, Belajar Curves Masalah 1:

Tangki eksternal awal untuk NASA Space Shuttle waktu 400 jam kerja untuk memproduksi. Tingkat pembelajaran adalah 80%. Berapa lama tangki kedua puluh ambil? Masalah 2: Sebuah operasi memiliki 90% belajar kurva dan unit pertama yang diproduksi waktu 28 menit. Biaya tenaga kerja adalah $ 20 per jam. (a) Berapa lama unit kedua ambil? (b) Berapa banyak yang harus biaya unit kedua? Masalah 3: Menggunakan data dari Soal 1, berapa lama waktu yang dibutuhkan untuk menghasilkan semua 20 tank?

Practice Problems: Supplement 7, Capacity Planning Problem 1: The design capacity for engine repair in our company is 80 trucks/day. The effective capacity is 40 engines/day and the actual output is 36 engines/day. Calculate the utilization and efficiency of the operation. If the efficiency for next month is expected to be 82%, what is the expected output?

Problem 2: Given:

fixed = F = cost$1000

variable = V = cost$2/unit selling = P = price$4/unit Find the break-even point in $ and in units. Problem 3: Develop the break-even chart for Problem 2. Problem 4: Jack’s Grocery is manufacturing a “store brand” item that has a variable cost of $0.75 per unit and a selling price of $1.25 per unit. Fixed costs are $12,000. Current volume is 50,000 units. The Grocery can substantially improve the product quality by adding a new piece of equipment at an additional fixed cost of $5,000. Variable cost would increase to $1.00, but

their volume should increase to 70,000 units due to the higher quality product. Should the company buy the new equipment? Problem 5: What are the break-even points ($ and units) for the two processes considered in Problem 4? Problem 6: Develop a break-even chart for Problem 4. Problem 7: Good News! You are going to receive $6,000 in each of the next 5 years for sale of used machinery. A bank is willing to lend you the present value of the money in the meantime at discount of 10% per year. How much cash do you receive now? ANSWERS:

Problem 1:

Actual output36 Utilization Design == capacity80 =45%

Actual output36 Efficiency Effective == capacity40 =90%

(40)(0.82)32.8 Expected fficiency) = = Output engines/day (Effective capacity) (E

Problem 2:

401-1B 10001000 2 F = Break-even P V.5 ==== EP point($)($)$2,000

− Break-even 1000 F -42 ==== xPV BEPx point()()500

Problem 3:

Problem 4: Profit = TR – TC Option A: Stay as is:

Profit50,000*(1.25 .75)12,000$13,000. =−−=

Option B: Add equipment:

Profit70,000 *(1.251.00)17,000$500. =−−=

Therefore the company should continue as is with the present equipment as this returns a higher profit.. Problem 5: Using current equipment:

B ($)$30,000 12,00012,00012,000 F = − 0.75 1.25 10.600.40 P V 11==== −EP

PV 12,000 F === B 1.250.75 −− ()24,000 EPx

Using the new equipment

11 1.800.2 1.25 B 1.00 ($)$85,000. 17,00017,00017,000 F = − P V==== −EP

BEP( x) =

F 17,000 17,000 = = = 68,000. P − V 1.25 − 1.00 0.25

Problem 6:

Problem 7: The net present value factor for 10% and 5 years is 3.79

(3.79 = 0.909 + 0.826 + 0.751 + 0.683 + 0.621)

Therefore, the present value is: 3.79 * $6,000 = $22,740

The Bad News is you do have to pay back the loans!

Praktek Masalah: Tambahan 7, Perencanaan Kapasitas Masalah 1: Kapasitas desain untuk perbaikan mesin di perusahaan kami adalah 80 truk / hari. Kapasitas efektif adalah 40 mesin / hari dan output sebenarnya 36 mesin / hari. Hitung pemanfaatan dan efisiensi operasi. Jika efisiensi untuk bulan depan diharapkan menjadi 82%, apa output yang diharapkan? Masalah 2: Mengingat:

Carilah titik impas dalam $ dan dalam satuan.

Masalah 3: Mengembangkan tabel impas untuk Soal 2. Masalah 4: Jack Grocery adalah manufaktur "merek toko" item yang memiliki biaya variabel sebesar $ 0,75 per unit dan harga jual sebesar $ 1,25 per unit. Biaya tetap adalah $ 12.000. volume saat ini adalah 50.000 unit. The Grocery secara substansial dapat meningkatkan kualitas produk dengan menambahkan sepotong peralatan baru dengan biaya tetap tambahan sebesar $ 5.000. biaya variabel akan meningkat menjadi $ 1,00, tetapi volume mereka harus meningkat menjadi 70.000 unit karena kualitas produk yang lebih tinggi. Jika perusahaan membeli peralatan baru? Masalah 5: Apa titik impas ($ dan unit) untuk dua proses dipertimbangkan dalam Soal 4? Masalah 6: Mengembangkan bagan impas untuk Soal 4. Masalah 7: Good News! Anda akan menerima $ 6.000 dalam setiap 5 tahun ke depan untuk penjualan mesin yang digunakan. Sebuah bank bersedia meminjamkan nilai tunai dari uang sementara di diskonto 10% per tahun. Berapa uang tunai yang Anda terima sekarang?