Taylmod aff

Page 1

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Page 277

16. cj

Basic Variables

300

400

0

0

0

Quantity

x1

x2

s1

s2

s3

0

s1

18

3

2

1

0

0

0

s2

20

2

4

0

1

0

0

s3

4

0

1

0

0

1

zj

0

0

0

0

0

0

cj – zj

300

400

0

0

0

Basic Variables

300

400

0

0

0

Quantity

x1

x2

s1

s2

s3

cj

0

s1

10

3

0

1

0

–2

0

s2

4

2

0

0

1

–4

400

x2

4

0

1

0

0

1

zj

1,600

0

400

0

0

400

cj – zj

300

0

0

0

–400

Basic Variables

300

400

0

0

0

Quantity

x1

x2

s1

s2

s3

cj

0

s1

4

0

0

1

–3/2

4

300

x1

2

1

0

0

1/2

–2

400

x2

4

0

1

0

0

1

zj

2,200

300

400

0

150

–200

0

0

0

–150

200

300

400

0

0

0

Quantity

x1

x2

s1

s2

s3

cj – zj cj

Basic Variables 0

s3

1

0

0

1/4

–3/8

1

300

x1

4

1

0

1/2

–1/4

0

400

x2

3

0

1

–1/4

3/8

0

zj

2,400

300

400

50

75

0

0

0

–50

–75

0

cj – zj Optimal

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17. cj

Basic Variables

Quantity

5

4

0

0

x1

x2

s1

s2

0

s1

150

3/10

1/2

1

0

0

s2

2,000

10

4

0

1

zj

0

0

0

0

0

cj – zj

5

4

0

0

Basic Variables

5

4

0

0

x1

x2

s1

s2

cj

Quantity

0

s1

90

0 19/50

1 –3/100

5

x1

200

1

2/5

0

1/10

zj

1,000

5

2

0

1/2

0

2

0

–1/2

5

4

0

0

Quantity

x1

x2

s1

s2

cj – zj cj

Basic Variables

4

x2

4,500/19

0

1

5

x1

2,000/19

1

0 –20/19

zj

28,000/19

5

4 100/19 13/28

0

0 –100/19 –13/38

cj – zj

50/19 –3/38 5/38

Optimal 18. cj

Basic Variables

100

150

0

0

0

Quantity

x1

x2

s1

s2

s3

0

s1

160

10

4

1

0

0

0

s2

20

1

1

0

1

0

0

s3

300

10

20

0

0

1

zj

0

0

0

0

0

0

100

150

0

0

0

cj – zj

(continued)

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Basic Variables

Page 279

100

150

0

0

0

Quantity

x1

x2

s1

s2

s3

0

s1

100

8

0

1

0

–1/5

0

s2

5

1/2

0

0

1

–1/20

150

x2

15

1/2

1

0

0

1/20

zj

2,250

75

150

0

0

15/2

cj – zj

25

0

0

0

–15/2

Basic Variables

100

150

0

0

0

Quantity

x1

x2

s1

s2

s3

cj

0

s1

20

0

0

1

–16

3/5

100

x1

10

1

0

0

2

–1/10

150

x2

10

0

1

0

–1

1/10

zj

2,500

100

150

0

50

5

0

0

0

–50

–5

100

20

60

0

0

0

Quantity

x1

x2

x3

s1

s2

s3

cj – zj Optimal 19. cj

Basic Variables

0

s1

60

3

5

0

1

0

0

0

s2

100

2

2

2

0

1

0

0

s3

40

0

0

1

0

0

1

zj

0

0

0

0

0

0

0

cj – zj

100

20

60

0

0

0

Basic Variables

100

20

60

0

0

0

Quantity

x1

x2

x3

s1

s2

s3

cj

100

x1

20

1

5/3

0

1/3

0

0

0

s2

60

0

–4/3

2

–2/3

1

0

0

s3

40

0

0

1

0

0

1

zj

2,000

100

500/3

0

100/3

0

0

60 –100/3

0

0

cj – zj

0 –440/3

(continued)

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Basic Variables

Page 280

100

20

60

0

0

0

Quantity

x1

x2

x3

s1

s2

s3

100

x1

20

1

5/3

0

1/3

0

0

60

x3

30

0

–2/3

1

–1/3

1/2

0

0

s3

10

0

2/3

0

1/3

–1/2

1

zj

3,800

100

380/3

60

40/3

30

0

0 –320/3

0

–40/3

–30

0

cj – zj Optimal 20.

a. b. c. d. e.

maximization, because cj – zj x2 = 10, s2 = 20, x1 = 10, Z = 30 maximize Z = x1 + 2x2 – x3 3 No, because there are three constraints and three “slack” variables f. s1 = 0 g. yes, because cj – zj = 0 for s1 h. x2 = 3 1/3, s2 = 26 2/3, x1 = 23 1/3, Z = 30

21. cj

Basic Variables

120

40

240

0

0

M

M

Quantity

x1

x2

x3

s1

s2

A1

A2

M

A1

27

4

1

3

–1

0

1

0

M

A2

30

2

6

3

0

–1

0

1

zj

54M

6M

7M

6M

–M

–M

M

M

7M – 40 6M – 240 –M

–M

0

0

zj – cj cj

Basic Variables

6M – 120

Quantity

120

40

240

0

0

M

x1

x2

x3

s1

s2

A1

M

A1

22

11/3

0

5/2

–1

1/6

1

40

x2

5

1/3

1

1/2

0

–1/6

0

zj

19M + 200

11M/3 + 40/3

40

5M/2 + 20

–M

M/6 – 20/3

M

11M/3 – 320/3

0

5M/2 – 220

–M

M/6 – 20/3

0

zj – cj cj

Basic Variables

120

40

240

0

0

Quantity

x1

x2

x3

s1

s2

120

x1

6

1

0

15/22

–3/11

1/22

40

x2

3

0

1

6/22

1/11

–2/11

zj

840

120

40

1,020/11 –320/11

–20/11

0 –1,620/11 –320/11

–20/11

cj – zj

0

Optimal 280


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22. cj

Basic Variables

.05

.10

0

0

M

M

Quantity

x1

x2

s1

s2

A1

A2

M

A1

36

6

2

–1

0

1

0

M

A2

50

5

5

0

–1

0

1

86M

11M

7M

–M

–M

M

M

11M – .05

7M – .10

–M

–M

0

0

zj zj – cj

cj

Basic Variables

.05

.10

0

0

M

Quantity

x1

x2

s1

s2

A2

.05

x1

6

1

1/3

–1/6

0

0

M

A2

20

0

10/3

5/6

–1

1

zj

20M + .3

zj – cj cj

Basic Variables

.05

10M/3 + .02

5M/6 – .01

–M

M

0

10M/3 – .08

5M/6 – .01

–M

0

.05

.10

0

0

Quantity

x1

x2

s1

s2

.05

x1

4

1

0

–1/4 1/10

.10

x2

6

0

1

1/4 –3/10

zj

.80

.05

.10

.0125 –.025

0

0

.0125 –.025

.05

.10

0

0

Quantity

x1

x2

s1

s2

zj – cj cj

Basic Variables

.05

x1

10

1

1

0 –1/5

0

s1

24

0

4

1 –6/5

zj

.50

.05

.05

0 –.01

0

–.05

0 –.01

zj – cj Optimal

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23. x2 24 20 16 12 Third tableau

8 4

0

4 First tableau

8

12 16 20 Fourth tableau Second tableau

24

28

32

x1

24. cj

Basic Variables

10

12

7

0

0

0

Quantity

x1

x2

x3

s1

s2

s3

0

s1

300

20

15

10

1

0

0

0

s2

120

10

5

0

0

1

0

0

s3

40

1

0

2

0

0

1

zj

0

0

0

0

0

0

0

cj – zj

10

12

7

0

0

0

Basic Variables

10

12

7

0

0

0

Quantity

x1

x2

x3

s1

s2

s3

cj

12

x2

20

4/3

1

2/3

1/15

0

0

0

s2

20

10/3

0

–10/3

–1/3

1

0

0

s3

40

1

0

2

0

0

1

zj

240

16

12

8

4/5

0

0

–6

0

–1

–4/5

0

0

cj – zj Optimal

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25. cj

Basic Variables

6

2

12

0

0

Quantity

x1

x2

x3

s1

s2

0

s1

24

4

1

3

1

0

0

s2

30

2

6

3

0

1

zj

0

0

0

0

0

0

cj – zj

6

2

12

0

0

Basic Variables

6

2

12

0

0

Quantity

x1

x2

x3

s1

s2

cj

12

x3

8

4/3

1/3

1

1/3

0

0

s2

6

–2

5

0

–1

1

zj

96

16

4

12

4

0

–10

–2

0

–4

0

cj – zj Optimal

26. cj

Basic Variables

100

75

90

95

0

0

0

0

Quantity

x1

x2

x3

x4

s1

s2

s3

s4

0

s1

40

3

2

0

0

1

0

0

0

0

s2

25

0

0

4

1

0

1

0

0

0

s3

2,000

200

0

250

0

0

0

1

0

0

s4

2,200

100

0

0

200

0

0

0

1

zj

0

0

0

0

0

0

0

0

0

cj – zj

100

75

90

95

0

0

0

0

Basic Variables

100

75

90

95

0

0

0

0

Quantity

x1

x2

x3

x4

s1

s2

s3

s4

cj

0

s1

10

0

2 –3.75

0

1

0 –.015

0

0

s2

25

0

0

4

1

0

1

0

0

100

x1

10

1

0

1.25

0

0

0

.005

0

0

s4

1,200

0

0 –1.25

200

0

0

–.50

1

zj

1,000

100

0

1.25

0

0

0

.50

0

0

75

–35

95

0

0

–.50

0

cj – zj

(continued)

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Basic Variables

Page 284

100

75

90

95

0

0

0

0

Quantity

x1

x2

x3

x4

s1

s2

s3

s4 0

0

s1

10

0

2 –3.75

0

1

0 –.015

0

s2

19

0

0

4.6

0

0

1

.002 –.005

100

x1

10

1

0

1.25

0

0

0

.005

0

95

x4

6

0

0 –.625

1

0

0 –.002

.005

zj

1,570

100

0

65.6

95

0

0

.475

0

75

24.4

0

0

0

100

75

90

95

0

0

0

0

Quantity

x1

x2

x3

x4

s1

s2

s3

s4

0 –.007

0

cj – zj cj

Basic Variables

.26

–.26 –.475

75

x2

5

0

1 –1.875

0

.50

0

s2

19

0

0

4.6

0

0

1

.002 –.005

100

x1

10

1

0

1.25

0

0

0

.005

0

95

x4

6

0

0 –.625

1

0

0 –.002

.005

zj

1,945

100

75

–75

95

37.5

0

.475

0

0

165

0 –37.5

0

100

75

90

95

0

0

0

0

x1

x2

x3

x4

s1

s2

s3

s4

cj – zj cj

Basic Variables

Quantity

–.30

.30 –.475

75

x2

12.7

0

1

0

0

.5

.405 –.006 –.002

90

x3

4.1

0

0

1

0

0

.216

100

x1

4.9

1

0

0

0

0 –.270

95

x4

8.6

0

0

0

1

zj

2,623

100

75

90

95

0

0

0

100

75

90

95

0

0

0

0

Quantity

x1

x2

x3

x4

s1

s2

s3

s4

0

0

cj – zj cj

Basic Variables

.001 –.001 .004

.001

0

.135 –.002

.004

37.5

35.7 –.211

.297

0 –37.5 –35.7

.211 –.297

75

x2

20

1.5

1

0

0

.50

0

90

x3

3.5

–.125

0

1

0

0

.25

0

s3

1,125

231.25

0

0

0

0 –62.5

1

.313

95

x4

11

.50

0

0

1

0

0

0

.005

zj

2,860

148.75

75

90

95

37.5

22.5

0

.36

–48.75

0

0

0 –37.5 –22.5

0

–.36

cj – zj Optimal

284

0 –.001


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27. cj

Basic Variables

20

16

0

0

0

M

M

M

Quantity

x1

x2

s1

s2

s3

A1

A2

A3

M

A1

6

3

1

–1

0

0

1

0

0

M

A2

4

1

1

0

–1

0

0

1

0

M

A3

12

2

6

0

0

–1

0

0

1

22M

6M

8M

–M

–M

–M

M

M

M

8M – 16

–M

–M

–M

0

0

0

zj zj – cj

cj

Basic Variables

6M – 20

20

16

0

0

0

M

M

Quantity

x1

x2

s1

s2

s3

A1

A2

M

A1

4

8/3

0

–1

0

1/6

1

0

M

A2

2

2/3

0

0

–1

1/6

0

1

16

x2

2

1/3

1

0

0

–1/6

0

0

10M/3 + 16/3

16

–M

–M

M/3 – 8/3

M

M

10M/3 – 44/3

0

–M

–M

M/3 – 8/3

0

0

zj

32 + 6M

zj – cj

cj

Basic Variables

20

16

0

0

0

M

Quantity x1

x2

s1

s2

s3

A2

20

x1

3/2

1

0

–3/8

0

1/16

0

M

A2

1

0

0

1/4

–1

1/8

1

16

x2

3/2

0

1

1/8

0

–3/16

0

zj

M + 27

20

16

M/4 – 53/6

–M + 16/3

M/8 – 25/12

M

0

0

M/4 – 53/6

–M + 16/3

M/8 – 25/12

0

zj – cj

(continued)

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Basic Variables

Page 286

20

16

0

0

0

Quantity

x1

x2

s1

s2

s3

20

x1

3

1

0

0

–3/2

1/4

0

s1

4

0

0

1

–4

1/2

16

x2

1

0

1

0

1/2

–1/4

zj

76

20

16

0

–22

1

zj – cj

0

0

0

–22

1

Basic Variables

20

16

0

0

0

Quantity

x1

x2

s1

s2

s3

cj

20

x1

1

1

0

–1/2

1/2

0

0

s3

8

0

0

2

–8

1

16

x2

3

0

1

1/2

–3/2

0

zj

68

20

16

–2

–14

0

0

0

–2

–14

0

zj – cj Optimal

28. x2 12 10 8 6 4

Fifth tableau Third tableau

2

Fourth tableau

Second tableau 0

2 4 First tableau

6

8

10

12

14

16

x1

29. Minimize Z = 8x1 + 2x2 + 7x3 + 0s1 + 0s2 + 0s3 – MA1 – MA2 – MA3 subject to 2x1 + 6x2 + x3 + A1 = 30 3x2 + 4x3 – s1 + A2 = 60 4x1 + x2 + 2x3 + s2 = 50 x1 + 2x2 – s3 + A3 = 20 x1, x2, x3 ≥ 0

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30. Minimize Z = 40x1 + 55x2 + 30x3 + 0s1 + 0s2 + 0s3 + MA1 + MA2 + MA3 subject to x1 + 2x2 + 3x3 + s1 = 60 2x1 + x2 + x3 + A1 = 40 x1 + 3x2 + x3 – s2 + A2 = 50 5x2 –3x3 – s3 + A3 = 100 x1, x2, x3 ≥ 0

31. cj

Basic Variables

40

60

0

0

0

0

–M

–M

Quantity

x1

x2

s1

s2

s3

s4

A1

A2

0

s1

30

1

2

1

0

0

0

0

0

0

s2

72

4

4

0

1

0

0

0

0

–M

A1

5

1

0

0

0

–1

0

1

0

–M

A2

12

0

1

0

0

0

–1

0

1

–17M

–M

–M

0

0

M

M

–M

–M

0

0

–M

–M

0

0

zj cj – zj cj

Basic Variables

M + 40

M + 60

40

60

0

0

0

0

–M

Quantity

x1

x2

s1

s2

s3

s4

A1

0

s1

6

1

0

1

0

0

2

0

0

s2

24

4

0

0

1

0

4

0

–M

A1

5

1

0

0

0

–1

0

1

60

x2

12

0

1

0

0

0

–1

0

zj

–5M + 720

–M

60

0

0

M

–60

–M

0

0

0

–M

60

0

cj – zj cj

Basic Variables

M + 40 40

60

0

0

0

0

Quantity

x1

x2

s1

s2

s3

s4

0

s1

1

0

0

1

0

1

2

0

s2

4

0

0

0

1

4

4

40

x1

5

1

0

0

0

–1

0

60

x2

12

0

1

0

0

0

–1

zj

920

40

60

0

0

–40

–60

0

0

0

0

40

60

cj – zj

(continued)

287


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cj

8:50 PM

Basic Variables

Page 288

40

60

0

0

0

0

Quantity

x1

x2

s1

s2

s3

s4

0

s4

1/2

0

0

1/2

0

1/2

1

0

s2

2

0

0

–2

1

2

0

40

x1

5

1

0

0

0

–1

0

60

x2

25/2

0

1

1/2

0

1/2

0

zj

950

40

60

30

0

–10

0

cj – zj

0

0

–30

0

10

0

Basic Variables

40

60

0

0

0

0

Quantity

x1

x2

s1

s2

s3

s4

cj

0

s4

0

0

0

1

–1/4

0

1

0

s3

1

0

0

–4

1/2

1

0

40

x1

6

1

0

–1

1/2

0

0

60

x2

12

0

1

1

–1/4

0

0

zj

960

40

60

20

5

0

0

0

0

–20

–5

0

0

cj – zj

Tie

Optimal 32. cj

Basic Variables

1

5

0

0

0

–M

Quantity

x1

x2

s1

s2

s3

A1

–M

A1

25

5

5

–1

0

0

1

0

s2

16

2

4

0

1

0

0

0

s3

5

1

0

0

0

1

0

zj

–25M

–5M

–5M

M

0

0

–M

5M + 1

5M + 5

–M

0

0

0

cj – zj cj

Basic Variables

1

5

0

0

0

–M

Quantity

x1

x2

s1

s2

s3

A1

–M

A1

5

5/2

0

–1

–5/4

0

1

5

x2

4

1/2

1

0

1/4

0

0

0

s3

5

1

0

0

0

1

0

–5M + 20 –5M/2 + 5/2

5

M

–5M/4 + 5/4

0

–M

5M/2 – 3/2

0

–M

5M/4 – 5/4

0

0

zj cj – zj

(continued) 288


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4/21/06

cj

8:50 PM

Basic Variables

Page 289

1

5

0

0

0

Quantity

x1

x2

s1

s2

s3

1

x1

2

1

0

–2/5

–1/2

0

5

x2

3

0

1

1/5

1/2

0

0

s3

3

0

0

2/5

1/2

1

zj

17

1

5

3/5

2

0

0

0

–3/5

–2

0

cj – zj Optimal

33. cj

Basic Variables

3

6

0

0

0

0

M

Quantity

x1

x2

s1

s2

s3

s4

A1

0

s1

18

3

2

1

0

0

0

0

M

A1

5

1

1

0

–1

0

0

1

0

s3

4

1

0

0

0

1

0

0

0

s4

7

0

1

0

0

0

1

0

zj

5M

M

M

0

–M

0

0

M

zj – cj

M–3

M–6

0

–M

0

0

0

Basic Variables

3

6

0

0

0

0

M

Quantity

x1

x2

s1

s2

s3

s4

A1

cj

0

s1

6

0

2

1

0

–3

0

0

M

A1

1

0

1

0

–1

–1

0

1

3

x1

4

1

0

0

0

1

0

0

0

s4

7

0

1

0

0

0

1

0

zj

M + 12

3

M

0

–M

–M + 3

0

M

zj – cj

0

M–6

0

–M

–M + 3

0

0

Basic Variables

3

6

0

0

0

0

Quantity

x1

x2

s1

s2

s3

s4

cj

0

s1

4

0

0

1

2

–1

0

6

x2

1

0

1

0

–1

–1

0

3

x1

4

1

0

0

0

1

0

0

s4

6

0

0

0

1

1

1

zj

18

3

6

0

–6

–3

0

0

0

0

–6

–3

0

zj – cj Optimal

289


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Page 290

34. cj

Basic Variables

10

5

0

0

–M

–M

Quantity

x1

x2

s1

s2

A1

A2

–M

A1

10

2

1

–1

0

1

0

–M

A2

4

0

1

0

0

0

1

0

s2

20

1

4

0

1

0

0

zj

–14M

–2M

–2M

M

0

–M

–M

2M + 10

2M + 5

–M

0

0

0

cj – zj cj

Basic Variables

10

5

0

0

–M

Quantity

x1

x2

s1

s2

A2

10

x1

5

1

1/2

–1/2

0

0

–M

A2

4

0

1

0

0

1

0

s2

15

0

7/2

1/2

1

0

zj

–4M + 50

10

–M + 5

–5

0

–M

5

0

0

cj

cj – zj

0

M

Basic Variables

10

5

0

0

Quantity

x1

x2

s1

s2

10

x1

3

1

0

–1/2

0

5

x2

4

0

1

0

0

0

s2

1

0

0

1/2

1

zj

50

10

5

–5

0

cj – zj

0

0

5

0

Basic Variables

10

5

0

0

Quantity

x1

x2

s1

s2

cj

10

x1

4

1

0

0

1

5

x2

4

0

1

0

0

0

s1

2

0

0

1

2

zj

60

10

5

0

10

0

0

0 –10

cj – zj Optimal

290


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Page 291

35. cj

Basic Variables

1

2

–1

0

0

0

Quantity

x1

x2

x3

s1

s2

s3

0

s1

40

0

4

1

1

0

0

0

s2

20

1

–1

0

0

1

0

0

s3

60

2

4

3

0

0

1

zj

0

0

0

0

0

0

0

cj – zj

1

2

–1

0

0

0

Basic Variables

1

2

–1

0

0

0

Quantity

x1

x2

x3

s1

s2

s3

cj

2

x2

10

0

1

1/4

1/4

0

0

0

s2

30

1

0

1/4

1/4

1

0

0

s3

20

2

0

2

–1

0

1

zj

20

0

2

1/2

1/2

0

0

cj – zj

1

0

–3/2

–1/2

0

0

Basic Variables

1

2

–1

0

0

0

Quantity

x1

x2

x3

s1

s2

s3

cj

2

x2

10

0

1

1/4

1/4

0

0

0

s2

30

0

0

–3/4

3/4

1

–1/2

1

x1

10

1

0

1

–1/2

0

1/2

zj

30

1

2

3/2

0

0

1/2

0

0

–5/2

0

0

–1/2

1

2

–1

0

0

0

x1

x2

x3

s1

s2

s3

cj – zj Multiple optimum solution Alternate solution: cj

Basic Variables

Quantity

2

x2

10/3

0

1

1/2

0

–1/3

1/6

0

s1

80/3

0

0

–1

1

4/3

–2/3

1

x1

70/3

1

0

1/2

0

2/3

1/6

zj

30

1

2

3/2

0

0

1/2

0

0

–5/2

0

0

–1/2

cj – zj

291


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Page 292

36. cj

Basic Variables

1

2

2

0

0

–M

–M

Quantity

x1

x2

x3

s1

s2

A1

A2

0

s1

12

1

1

2

1

0

0

0

–M

A1

20

2

1

5

0

0

1

0

–M

A2

8

1

1

–1

0

–1

0

1

–28M

–3M

–2M

–4M

0

M

–M

–M

0

–M

0

0

zj

cj

cj – zj

1 + 3M

2 + 2M 2 + 4M

Basic Variables

1

2

2

0

0

–M

Quantity

x1

x2

x3

s1

s2

A2

0

s1

4

1/5

3/5

0

1

0

0

2

x3

4

2/5

1/5

1

0

0

0

–M

A2

12

7/5

6/5

0

0

–1

1

zj

cj

–12M + 8 –4/5 – 7M/5

2/5 – 6M/5

2

0

M

–M

cj – zj

1/5 + 7M/5

8/5 + 6M/5

0

0

–M

0

Basic Variables

1

2

2

0

0

x1

x2

x3

s1

s2

Quantity

0

s1

16/7

0

3/7

0

1

1/7

2

x3

4/7

0

–1/7

1

0

2/7

1

x1

60/7

1

6/7

0

0

–5/7

zj

68/7

1

4/7

2

0

–1/7

cj – zj

0

10/7

0

0

1/7

Basic Variables

1

2

2

0

0

x1

x2

x3

s1

s2

cj

Quantity

2

x2

16/3

0

1

0

7/3

1/3

2

x3

4/3

0

0

1

1/3

1/3

1

x1

4

1

0

0

–2

–1

zj

52/3

1

2

2

10/3

1/3

0

0

0

–10/3

–1/3

cj – zj Optimal

292


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Page 293

37. cj

Basic Variables

400

350

450

0

0

0

0

Quantity

x1

x2

x3

s1

s2

s3

s4

0

s1

120

2

3

2

1

0

0

0

0

s2

160

4

3

1

0

1

0

0

0

s3

100

3

2

4

0

0

1

0

0

s4

40

1

1

1

0

0

0

1

zj

0

0

0

0

0

0

0

0

cj – zj

400

350

450

0

0

0

0

Basic Variables

400

350

450

0

0

0

0

Quantity

x1

x2

x3

s1

s2

s3

s4

cj

0

s1

70

1/2

2

0

1

0

–1/2

0

0

s2

135

13/4

5/2

0

0

1

–1/4

0

450

x3

25

3/4

1/2

1

0

0

1/4

0

0

s4

15

–1/4

1/2

0

0

0

–1/4

1

zj

11,250

1,350/4 450/2

450

0

0 450/4

0

250/4 250/2

0

0

0 –450/4

0

cj – zj cj

Basic Variables

Quantity

400

350

450

0

0

0

0

x1

x2

x3

s1

s2

s3

s4

0

s1

10

–1/2

0

0

1

0

1/2

–4

0

s2

60

2

0

0

0

1

1

–5

450

x3

10

1/2

0

1

0

0

1/2

–1

350

x2

30

1/2

1

0

0

0

–1/2

2

zj

15,000

400

350

450

0

0

50

250

0

0

0

0

0

–50

–250

400

350

450

0

0

0

0

Quantity

x1

x2

x3

s1

s2

s3

s4

cj – zj Multiple optimum solution at x1 Alternate solution: cj

Basic Variables 0

s1

20

0

0

1

1

0

1

–5

0

s2

20

0

0

–4

0

1

–1

–1

400

x1

20

1

0

2

0

0

1

–2

350

x2

20

0

1

–1

0

0

–1

3

zj

15,000

400

350

450

0

0

50

250

0

0

0

0

0

–50

–250

cj – zj

293


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Page 294

38. (a) x2 5

Infeasible-no common solution space 4 3 2 1

0

1

2

3

4

5

6

7

x1

(b) cj

Basic Variables

3

2

0

0

–M

Quantity

x1

x2

s1

s2

A1

0

s1

1

1

1

1

0

0

–M

A1

2

1

1

0

–1

1

–2M

–M

–M

0

M

–M

cj – zj

M+3

M+2

0

–M

0

Basic Variables

3

2

0

0

–M

Quantity

x1

x2

s1

s2

A1

zj

cj

3

x1

1

1

1

1

0

0

–M

A1

1

0

0

–1

–1

1

zj

3–M

3

3

M

M

–M

0

–1

–M

–M

0

cj – zj Infeasible solution

39. (a) x2 5 4 3

Unbounded solution

2 1

-4

-3

-2

-1

Z 0

1

2

3

4

5

6

x1

294


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Page 295

(b) cj

Basic Variables

1

1

0

0

Quantity

x1

x2

s1

s2

0

s1

1

–1

1

1

0

0

s2

4

–1

2

0

1

zj

0

0

0

0

0

1

1

0

0

cj – zj

Tie for entering variable; if x1 is chosen, the solution is unbounded. Select x2 arbitrarily. cj

Basic Variables

1

1

0

0

Quantity

x1

x2

s1

s2

1

x2

1

–1

1

1

0

0

s2

3

1

0

–1

1

zj

1

–1

1

1

0

cj – zj

2

0

–1

0

Basic Variables

1

1

0

0

Quantity

x1

x2

s1

s2

cj

1

x2

4

0

1

0

1

1

x1

3

1

0

–1

1

zj

7

1

1

–1

2

0

0

1

–2

cj – zj Unbounded; no pivot row available

40. cj

Basic Variables

7

5

5

0

0

0

0

Quantity

x1

x2

x3

s1

s2

s3

s4

0

s1

25

1

1

1

1

0

0

0

0

s2

40

2

1

1

0

1

0

0

0

s3

25

1

1

0

0

0

1

0

0

s4

6

0

0

1

0

0

0

1

zj

0

0

0

0

0

0

0

0

7

5

5

0

0

0

0

cj – zj

(continued)

295


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cj

8:50 PM

Basic Variables

Page 296

7

5

5

0

0

0

0

Quantity

x1

x2

x3

s1

s2

s3

s4

0

s1

5

0

1/2

1/2

1

–1/2

0

0

7

x1

20

1

1/2

1/2

0

1/2

0

0

0

s3

5

0

1/2

–1/2

0

–1/2

1

0

0

s4

6

0

0

0

0

0

0

1

zj

140

7

7/2

7/2

0

7/2

0

0

0

3/2

3/2

0

–7/2

0

0

cj – zj

Tie cj

Basic Variables

7

5

5

0

0

0

0

Quantity

x1

x2

x3

s1

s2

s3

s4

5

x2

10

0

1

1

2

–1

0

0

7

x1

15

1

0

0

–1

1

0

0

0

s3

0

0

0

–1

–1

0

1

0

0

s4

6

0

0

1

0

0

0

1

zj

155

7

5

5

3

2

0

0

0

0

0

–3

–2

0

0

cj – zj Multiple optimum

(continued)

Alternate Solution: cj

Basic Variables

7

5

5

0

0

0

0

Quantity

x1

x2

x3

s1

s2

s3

s4

5

x2

4

0

1

0

2

–1

0

–1

7

x1

15

1

0

0

–1

1

0

0

0

s3

6

0

0

0

–1

0

1

1

5

x3

6

0

0

1

0

0

0

1

zj

155

7

5

5

3

2

0

0

0

0

0

–3

–2

0

0

cj – zj

296


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Page 297

41. cj

Basic Variables

15

25

0

0

0

M

Quantity

x1

x2

s1

s2

s3

A1

M A2

M

A1

12

3

4

–1

0

0

1

0

M

A2

6

2

1

0

–1

0

0

1

0

s3

9

3

2

0

0

1

0

0

zj

18M

5M

5M

–M

–M

0

M

M

5M – 25

–M

–M

0

0

zj – cj cj

Basic Variables

5M – 15

0

15

25

0

0

0

M

Quantity

x1

x2

s1

s2

s3

A1

M

A1

3

0

5/2

–1

1

0

1

15

x1

3

1

1/2

0

0

0

0

0

s3

0

0

1/2

0

0

1

0

15

5M/2 + 15/2

–M

3M/2 – 15/2

0

M

0

5M/2 – 35/2

–M

3M/2 – 15/2

0

0

zj

3M + 45

zj – cj cj

Basic Variables

15

25

0

0

0

M

Quantity

x1

x2

s1

s2

s3

A1

M

A1

3

0

0

–1

–6

–5

1

15

x1

3

1

0

0

–2

–1

0

25

x2

0

0

1

0

3

2

0

15

15

–M

–6M +45

–5M +45

M

0

0

–M

–6M +45

–5M +45

0

zj

3M + 45

zj – cj Infeasible solution

42.

a). minimize Zd = 90y1 + 60y2 subject to y1 + 2y2 ≥ 6 4y1 + 2y2 ≥ 10 y1, y2 ≥ 0 b) y1 = the marginal value of one additional lb of brass = $1.33 y2 = the marginal value of one additional hr of labor = $2.33

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c) c1, basic: cj

6+∆

10

0

0

Quantity

x1

x2

s1

s2

x2

20

0

1

1/3

–1/6

x1

10

1

0

–1/3

2/3

6+∆

10

4/3 – ∆/3

7/3 + 2∆/3

0

0

–4/3 + ∆/3

–7/3 – 2∆/3

Basic Variables

10 6+∆

zj

260 + 10∆

cj – zj

Since c2 = 10 + ∆; ∆ = c2 – 10. Thus

Solving for the cj – zj inequalities:

c2 – 10 ≤ 14 c2 ≤ 24

–4/3 + ∆/3 ≤ 0 ∆/3 ≤ 4/3 ∆≤4

Summarizing, 6 ≤ c2 ≤ 24.

Since c1 = 6 + ∆; ∆ = c1 – 6. Thus c1 – 6 ≤ 4 c1 ≤ 10 –7/3 – 2∆/3 ≤ 0 –2∆/3 ≤ 7/3 –2∆ ≤ 7 ∆ ≥ –7/2

d) q1: 20 + ∆/3 ≥ 0 x1: ∆/3 ≥ –20 ∆ ≥ –60

x2:

10 – ∆/3 ≥ 0 –∆/3 ≥ –10 ∆ ≤ 30

Therefore, –60 ≤ ∆ ≤ 30. Since q1 = 90 + ∆ ∆ = q1 – 90 –60 ≤ q1 – 90 ≤ 30 30 ≤ q1 ≤ 120

Since c1 = 6 + ∆; ∆ = c1 – 6. Thus c1 – 6 ≥ –7/2 c1 ≥ 5/2 Summarizing, 5/2 ≤ c1 ≤ 10. c2, basic: 6

10 + ∆

0

0

Quantity

x1

x2

s1

s2

10 + ∆ x2

20

0

1

1/3

–1/6

6

10

1

0

–1/3

2/3

6

10 + ∆

4/3 + ∆/3

7/3 – ∆/6

0

0

–4/3 – ∆/3

–7/3 + ∆/6

cj

Basic Variables

x1 zj

280 + 20∆

cj – zj

Solving for the cj – zj inequalities:

q2:

–4/3 – ∆/3 ≤ 0 –∆/3 ≤ 4/3 ∆ ≥ –4

x2:

Since c2 = 10 + ∆; ∆ = c2 – 10. Thus

20 – ∆/6 ≥ 0 – ∆/6 ≥ –20 ∆ ≤ 120

x1: 10 + 2∆/3 ≥ 0 2∆/3 ≥ –10 ∆ ≥ –15

Therefore, –15 ≤ ∆ ≤ 120. Since

c2 – 10 ≥ –4 c2 ≥ 6 –7/3 + ∆/6 ≤ 0 ∆/6 ≤ 7/3 ∆ ≤ 14

q2 = 60 + ∆ ∆ = q2 – 60 –15 ≤ q2 – 60 ≤ 120 45 ≤ q2 ≤ 180

298


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e) The marginal value of 1 hr of labor is $2.33. From part d, the sensitivity range for q2, labor, is 45 ≤ q2 ≤ 180. Thus, the company would purchase up to 180 hr at the marginal value price.

c)

x2 60 50 40

43.

a) Minimize Zd = 500y1 + 800y2 subject to

30

10y1 + 34y2 ≥ 200 50y1 + 20y2 ≥ 300 y1, y2 ≥ 0

20

y1 = $4.13 = the marginal value of one additional lb of chili beans; y2 = $4.67 = the marginal value of one additional lb of ground beef. b)

50 40 30 20

A B 10

20 C 30

40

50

60

10

20 C 30

40

50

60

x1

The constraint line for chili beans rotates, creating a new, smaller solution space, and the optimal solution shifts from point B to point B´ where x1 = 21.43 and x2 = 3.57.

60

0

B B´ 0

x2

10

A

10

x1

Point C must become the optimal solution for x2 = 0; therefore the slope of the objective function must be greater than the slope of the constraint for ground beef, –34/20. Solving the following for the profit, p, of Razorback chili yields –p/300 = –34/20 p = $510 Thus, if the profit of Razorback chili is greater than $510, no Longhorn chili will be produced. The new optimal solution will be x1 = 23.5 and x2 = 0.

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d) c1, basic: cj

Basic Variables

200 + ∆

300

0

0

Quantity

x1

x2

s1

s2

300

x2

6

0

1

17/750

–1/150

200 + ∆

x1

20

1

0

–1/75

1/30

zj

5,800 + 20∆

200 + ∆ 300 310/75 – ∆/75

cj – zj

70/15 + ∆/30

0 –310/75 + ∆/75 –70/15 – ∆/30

0

Since c2 = 300 + ∆; ∆ = c2 – 300. Thus

Solving for the cj – zj inequalities:

c2 – 300 ≤ 700 c2 ≤ 1,000

–310/75 + ∆/75 ≤ 0 ∆/75 ≤ 3310/75 ∆ ≤ 310

Summarizing, 117.65 ≤ c2 ≤ 1,000.

Since c1 = 200 + ∆; ∆ = c1 – 200. Thus c1 – 200 ≤ 310 c1 ≤ 510 –70/15 – ∆/30 ≤ 0 –∆/30 ≤ 70/15 ∆ ≥ –140

e) q1: x2: 6 + 17∆/750 ≥ 0 x1: 20 – ∆/75 ≥ 0 17∆/750 ≥ –6 –∆/75 ≥ –20 ∆ ≥ –264.7 ∆ ≤ 1,500 Therefore, –264.7 ≤ ∆ ≤1,500. Since

Since c1 = 200 + ∆; ∆ = c1 – 200. Thus

q1 = 500 + ∆ ∆ = q1 – 500 –264.7 ≤ q1 – 500 ≤ 1,500 235.3 ≤ q1 ≤ 2,000

c1 – 200 ≥ –140 c1 ≥ 60 Summarizing, 60 ≤ c1 ≤ 510. c2, basic:

cj

Basic Variables

200

300 + ∆

0

0

Quantity

x1

x2

s1

s2

300 + ∆

x2

6

0

1

17/750

–1/150

200

x1

20

1

0

–1/75

1/30

zj

5,800 + 6∆

200

cj – zj

300 + ∆

0

0

310/75 + 17∆/750

70/15 – ∆/150

–310/75 – 17∆/750 –70/15 + ∆/150

Solving for the cj – zj inequalities:

q2:

–310/75 – 17∆/750 ≤ 0 –17∆/750 ≤ 310/75 ∆ ≥ –182.35

x2:

Since c2 = 300 + ∆; ∆ = c2 – 300. Thus

Therefore, –600 ≤ ∆ ≤ 900. Since

c2 – 300 ≥ –182.35 c2 ≥ 117.65 –70/15 + ∆/150 ≤ 0 ∆/150 ≤ 70/15 ∆ ≤ 700

6 – ∆/150 ≥ 0 x1: 20 + ∆/30 ≥ 0 – ∆/150 ≥ –6 ∆/30 ≥ –20 ∆ ≤ 900 ∆ ≥ –600 q2 = 800 + ∆ ∆ = q2 – 800 –600 ≤ q2 – 800 ≤ 900 200 ≤ q2 ≤ 1,700

300


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f) The marginal value of 1 lb of chili beans is $4.13. The sensitivity range for q1, chili beans, is 235.3 ≤ q1q ≤ 2,000. Thus, the company would purchase up to 2,000 lb at the marginal value price. g) Groundbeef h) No effect 44. a) Minimize Zd = 60y1 + 40y2 subject to 12y1 + 4y2 ≥ 9 4y1 + 8y2 ≥ 7 y1, y2 ≥ 0 b) y1 = the marginal value of one additional hr of process 1; y2 = the marginal value of one additional hr of process 2 For the s1 column, the cj – zj value of $.55 is the marginal value of 1 hr of process 1 production time. For the s2 column, the cj – zj value of $0.60 is the marginal value of 1 hr of process 2 production time.

c) cj, basic: cj

Basic Variables

9+∆

7

0

0

Quantity

x1

x2

s1

s2

9+∆

x1

4

1

0

1/10

–1/20

7

x2

3

0

1

–1/20

3/20

zj

57 + 4∆

9+∆

7

cj – zj

0

11/20 – ∆/10

12/20 + ∆/20

0 –11/20 – ∆/10 –12/20 + ∆/20

301


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Since c2 = 7 + ∆; ∆ = c2 – 7. Thus

Solving for the cj – zj inequalities:

c2 – 7 ≥ –4 c2 ≥ 3

–11/20 – ∆/10 ≤ 0 –∆/10 ≤ 11/20 –∆ ≤ 11/2 ∆ ≥ –11/2

Summarizing, 3 ≤ c2 ≤ 18.

Since c1 = 9 + ∆ , ∆ = c1 – 9. Thus

d) q1:

c1 – 9 ≥ 11/2 c1 ≥ 7/2 –12/20 + ∆/20 ≤ 0 ∆/20 ≤ 12/20 ∆ ≤ 12

x1: 4 + ∆/10 ≥ 0 ∆/10 ≥ –4 –∆ ≥ –80 ∆ ≥ –40

x2: 3 – ∆/20 ≥ 0 –∆/20 ≥ –3 –∆ ≥ –60 ∆ ≤ 60

Therefore, –40 ≤ ∆ ≤60. Since

Since c1 = 9 + ∆ , ∆ = c1 – 9. Thus

q1 = 60 + ∆ ∆ = q1 – 60 –40 ≤ q1 – 60 ≤ 60 20 ≤ q1 ≤ 120

c1 – 9 ≤ 12 c1 ≤ 12 Summarizing, 7/2 ≤ c1 ≤ 12. c2, basic: cj

Basic Variables

9

7+∆

0

0

Quantity

x1

x2

s1

s2

9

x1

4

1

0

1/10

–1/20

7+∆

x2

3

0

1

–1/20

3/20

zj

57 + 3∆

9

7+∆

11/20 – ∆/20

12/20 + 3∆/20

0

0

–11/20 + ∆/20

–12/20 – 3∆/20

cj – zj

Solving for the cj – zj inequalities:

q2:

–11/20 + ∆/20 ≤ 0 ∆/20 ≤ 11/20 ∆ ≤ 11

x1: 4 – ∆/20 ≥ 0 –∆/20 ≥ –4 –∆ ≥ –80 ∆ ≤ 80

Since c2 = 7 + ∆; ∆ = c2 – 7. Thus

x2: 3 +3 ∆/20 ≥ 0 3∆/20 ≥ –3 ∆ ≥ –20

Therefore, –20 ≤ ∆ ≤ 80. Since

c2 – 7 ≤ 11 c2 ≤ 18 –12/20 – 3∆/20 ≤ 0 –3∆/20 ≤ 12/20 ∆ ≥ –4

q2 = 40 + ∆ ∆ = q2 – 40 –20 ≤ q2 – 40 ≤ 80 20 ≤ q2 ≤ 120

302


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e) The marginal value of 1 hr of process 1 production time is $.55. The sensitivity range for q1, production hours, is 20 ≤ q1 ≤ 120. Thus, the company would purchase up to 120 hr at the marginal value price.

Point A must become the optimal solution for x1 = 0; therefore the slope of the objective function must be less than the slope of the constraint for labor, –2/5. Solving the following for the profit, p, of coffee tables gives –200/p = –2/5 p = $500

45. a) Minimize Zd = 180y1 + 135y2 subject to

Thus, if the profit for coffee tables is greater than $500, no end tables will be produced. The new optimal solution will be x1 = 0 and x2 = 36.

2y1 + 3y2 ≥ 200 5y1 + 3y2 ≥ 300 y1, y2 ≥ 0 d)

b) y1 = $33.33 = the marginal value of an additional hr of labor; y2 = $44.44 = the marginal value of an additional bd. ft. of wood

x2 60

c)

50

x2

40

A

60

30

B

50 20 40 10

A

B

30

C 0

20 10

C 0

10

20

30

40

50

60

70

80

90

100

x1

303

10

20

30

40

50

C´ 60

70

80

90

100

The constraint line for wood moves outward, creating a new solution space, and the optimal solution point shifts from point B to point B´ where x1 = 31.67 and x2 = 23.33.

x1


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e) c1, basic: cj

Basic Variables

200 + ∆

300

0

0

Quantity

x1

x2

s1

s2

300

x2

30

0

1

1/3

–2/9

200 + ∆

x1

15

1

0

–1/3

5/9

zj

12,000 + 15∆

200 + ∆ 300

cj – zj

0

0

100/3 – ∆/3

400/9 + 5∆/9

–100/3 + ∆/3 –400/9 – 5∆/9 Since c2 = 300 + ∆; ∆ = c2 – 300. Thus

Solving for the cj – zj inequalities: –100/3 + ∆/3 ≤ 0 ∆/3 ≤ 100/3 ∆ ≤ 100

c2 – 300 ≤ 200 c2 ≤ 500 Summarizing, 200 ≤ c2 ≤ 500.

Since c1 = 200 + ∆; ∆ = c1 – 200. Thus c1 – 200 ≤ 100 c1 ≤ 300 –400/9 – 5∆/9 ≤ 0 –5∆/9 ≤ 400/9 –∆ ≤ 80 ∆ ≥ –80

f) q1: x2: 30 + ∆/3 ≥ 0 ∆/3 ≥ –30 ∆ ≥ –90

x1: 15 – ∆/3 ≥ 0 –∆/3 ≥ –15 –∆ ≤ –45 ∆ ≤ 45

Therefore, –90 ≤ ∆ ≤ 45. Since

Since c1 = 200 + ∆; ∆ = c1 – 200. Thus

q1 = 180 + ∆ ∆ = q1 – 180 –90 ≤ q1 – 180 ≤ 45 90 ≤ q1 ≤ 225

c1 – 200 ≥ –80 c1 ≥ 120 Summarizing, 120 ≤ c1 ≤ 300. c2, basic: cj

Basic Variables

200

300 + ∆

0

0

Quantity

x1

x2

s1

s2

300 + ∆

x2

30

0

1

1/3

–2/9

200

x1

15

1

0

–1/3

5/9

zj

12,000 + 300∆

cj – zj

200

300 + ∆ 100/3 + ∆/3

400/9 – 2∆ /9

–100/3 – ∆/3

–400/9 + 2∆ /9

0

0

Solving for the cj – zj inequalities:

q2:

–100/3 – ∆/3 ≤ 0 –∆/3 ≤ 100/3 –∆ ≤ 100 ∆ ≥ –100

x2: 30 – 2∆/9 ≥ 0 x1: 15 + 5∆/9 ≥ 0 –2∆/9 ≥ –30 5∆/9 ≥ –15 –∆ ≥ –135 ∆ ≥ –27 ∆ ≤ 135

Since c2 = 300 + ∆; ∆ = c2 – 300. Thus

Therefore, –27 ≤ ∆ ≤ 135. Since

c2 – 300 ≥ –100 c2 ≥ 200 –400/9 + 2∆/9 ≤ 0 2∆/9 ≤ 400/9 ∆ ≤ 200

q2 = 135 + ∆ ∆ = q2 – 135 –27 ≤ q2 – 135 ≤ 135 108 ≤ q2 ≤ 270

304


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g) The marginal value of 1 lb of wood is $44.44. From part f, the sensitivity range for q2, wood, is 108 ≤ q2 ≤ 270. Thus, the company would purchase up to 270 bd. ft. of wood at the marginal value price. g) The marginal value of labor is $33.33 and the marginal value of wood is $44.44; thus, wood should be purchased. 46. a) Minimize Zd = 19y1 + 14y2 + 20y3 subject to 2y1 + y2 + y3 ≥ 70 y1 + y2 + 2y3 ≥ 80 y1, y2, y3 ≥ 0 b) y1 =$20 = the marginal value of an additional hr of production time; y2 =$0 = the marginal value of an additional lb of steel; y3 = $30 = the marginal value of an additional ft of wire

c) c1, basic: 70 + ∆

80

0

0

0

Quantity

x1

x2

s1

s2

s3

x1

6

1

0

2/3

0

–1/3

0

s2

1

0

0

–1/3

1

–1/3

80

x2

7

0

1

–1/3

0

2/3

zj

980 + 6∆

70 + ∆

80

20 + 2∆/3

0

30 – ∆/3

0

0

–20 – 2∆/3

0

–30 + ∆/3

cj

Basic Variables

70 + ∆

cj – zj

Solving for the cj – zj inequalities:

Solving for the cj – zj inequalities:

–20 – 2∆/3 ≤ 0 –2∆/3 ≤ 20 –∆ ≤ 30 ∆ ≥ –30

–20 + ∆/3 ≤ 0 ∆/3 ≤ 20 ∆ ≥ 60 Since c2 = 80 + ∆; ∆ = c2 – 80. Thus

Since c1 = 70 + ∆; ∆ = c1 – 70. Thus

c2 – 80 ≤ 60 c2 ≤ 140 –30 – 2∆/3 ≤ 0 –2∆/3 ≤ 30 –∆ ≤ 45 ∆ ≥ –45

c1 – 70 ≥ –30 c1 ≥ 40 –30 + ∆/3 ≤ 0 ∆/3 ≤ 30 ∆ ≤ 90 Since c1 = 70 + ∆; ∆ = c1 – 70. Thus

Since c2 = 80 + ∆; ∆ = c2 – 80. Thus

c1 – 70 ≤ 90 c1 ≤ 160

c2 – 80 ≥ –45 c2 ≥ 35

Summarizing, 40 ≤ c1 ≤ 160.

Summarizing, 35 ≤ c2 ≤ 140.

c2, basic: 305


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Basic Variables

Page 306

70

80 + ∆

0

0

0

Quantity

x1

x2

s1

s2

s3

70

x1

6

1

0

2/3

0

–1/3

0

s2

1

0

0

–1/3

1

–1/3

x2

7

0

1

–1/3

0

2/3

zj

980 + 7∆

70

80 + ∆

20 – ∆/3

0

30 + 2∆/3

0

0

–20 + ∆/3

0

–30 – 2∆/3

80 + ∆

cj – zj d) q1: x1:

6 + 2∆/3 ≥ 0 2∆/3 ≥ –6 ∆ ≥ –9

7 – ∆/3 ≥ 0 –∆/3 ≥ –7 –∆ ≥ –21 ∆ ≤ 21

x2:

s2:

1 – ∆/3 ≥ 0 –∆/3 ≥ –1 –∆ ≥ –3 ∆≤3

Therefore, –9 ≤ ∆ ≤ 3. Since q1 = 19 + ∆ ∆ = q1 – 19 –9 ≤ q1 – 19 ≤ 3 10 ≤ q1 ≤ 22 q2: x1:

6 + 0∆ ≥ 0

7 + 0∆ ≥ 0

x2:

s2:

1+∆≥0 ∆ ≥ –1

s2:

1 – ∆/3 ≥ 0 –∆/3 ≥ –1 –∆ ≥ –3 ∆≤3

Therefore, ∆ ≥ –1. Since q2 = 14 + ∆ ∆ = q2 – 14 q2 – 14 ≥ –1 q2 ≥ 13 q3: x1:

6 – ∆/3 ≥ 0 –∆/3 ≥ –6 –∆ ≥ –18 ∆ ≤ 18

x2:

7 + 2∆/3 ≥ 0 2∆/3 ≥ –7 ∆ ≥ –21/2

Therefore, –21/2 ≤ ∆ ≤ 3. Since q3 = 20 + ∆ ∆ = q3 – 20

–21/2 ≤ q3 – 20 ≤ 3 19/2 ≤ q3 ≤ 23

e) The sensitivity range for production hours is 10 ≤ q1 ≤ 22. Since 25 hr exceeds the upper limit of the range, it would change the optimal solution.

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47. a) Minimize Zd = 64y1 + 50y2 + 120y3 + 7y4 + 7y5 subject to 4y1 + 5y2 + 15y3 + y4 ≥ 9 8y1 + 5y2 + 8y3 + y5 ≥ 12 y1, y2, y3, y4, y5 ≥ 0 b) y1 = $.75 = the marginal value of one additional hr of labor for process 1; y2 = $1.20 = the marginal value of one additional hr of labor for process 2; y3, y4, y5 = $0; these resources have no value since there were units available which were not used.

c) c1, basic: Solving for the cj – zj inequalities: –3/4 + ∆/4 ≤ 0 ∆/4 ≤ 3/4 ∆≤3

–6/5 – 2∆/5 ≤ 0 –2∆/5 ≤ 6/5 ∆ ≥ –3

Since c1 = 9 + ∆; ∆ = c1 – 9. Thus –3 ≤ ∆ ≤ 3 –3 ≤ c1 – 9 ≤ 3 6 ≤ c1 ≤ 12 c2, basic: Solving for the cj – zj inequalities: –3/4 + ∆/4 ≤ 0 –∆/4 ≤ 3/4 ∆ ≥ –3

–6/5 + ∆/5 ≤ 0 ∆/5 ≤ 6/5 ∆≤6

Since c2 = 12 + ∆; ∆ = c1 – 12. Thus –3 ≤ c2 – 12 ≤ 6 9 ≤ c2 ≤ 18

d) q1: x1:

4 – ∆/4 ≥ 0 –∆/4 ≥ –4 ∆ ≤ 16

s5:

1 – ∆/4 ≥ 0 –∆/4 ≥ –1 ∆≤4

s4:

3 + ∆/4 ≥ 0 ∆/4 ≥ –3 ∆ ≥ –12

x2:

6 + ∆/4 ≥ 0 ∆/4 ≥ –6 ∆ ≥ –24

s3:

307

12 + 7∆/4 ≥ 0 7∆/4 ≥ –12 ∆ ≥ –6.86


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Summarizing, –24 < –12 < –6.86 ≤ ∆ ≤ 4 ≤ 16 and, therefore, –6.86 ≤ ∆ ≤ 4 Since q1 = 64 + ∆; ∆ = q1 – 64. Therefore, –6.86 ≤ ∆ q1 – 64 ≤ 4 57.14 ≤ q1 ≤ 68 e) q3: x1:

4 + 0∆ ≥ 0 0∆ ≥ –4 ∆≤∞

s4:

3 + 0∆ ≥ 0 ∆≤∞

s5:

1 + 0∆ ≥ 0 ∆≤∞

s3:

6 + 0∆ ≥ 0 ∆≤∞ –12 ≤ ∆ ≤ ∞ x2:

Since q3 = 120 + ∆; ∆ = q3 – 120. Therefore, –12 ≤ ∆ ≤ ∞ –12 ≤ q3 – 120 ≤ ∞ 108 ≤ q3 ≤ ∞ Since 100 pounds is less than the lower limit of the range, the optimal solution mix will change. s2 enters the solution and s3 leaves. The new solution is, x1 = 3.27 s2 = 1.82 s5 = 0.64 s4 = 3.73 x2 = 6.36 Z = 105.82 48. a) Minimize Zd = 120y1 + 160y2 + 100y3 + 40y4 subject to 2y1 + 4y2 + 3y3 + y4 ≥ 40 3y1 + 3y2 + 2y3 + y4 ≥ 35 2y1 + y2 + 4y3 + y4 ≥ 45 y1, y2, y3, y4 ≥ 0 b) y1, y2 = 0; y3 = $5 = the marginal value of 1 hr of operation 3 time; y4 = $25 = the marginal value of 1 ft2 of storage space c) It does not have an effect. In the alternate solution the dual values remain the same, i.e., y3 = $5 and y4 = $25.

308

12 + ∆ ≥ 0 ∆ ≥ –12


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d) c2, basic: cj

Basic Variables

Quantity

40

35 + ∆

45

0

0

0

0

x1

x2

x3

s1

s2

s3

s4

0

s1

10

–1/2

0

0

1

0

1/2

–4

0

s2

60

2

0

0

0

1

1

–5

45

x3

10

1/2

0

1

0

0

1/2

–1

x2

30

1/2

1

0

0

0

–1/2

2

zj

1,500 + 35∆

45

0

0

5 – ∆/2

0

0

0

35 + ∆

cj – zj

40 + ∆/2 35 + ∆ –∆/2

0

25 + 2∆

–5 + ∆/2 –25 – 2∆

Since c2 = 35 + ∆; ∆ = c2 – 35. Thus

Solving for the cj – zj inequalities: –∆/2 ≤ 0 ∆≥0

c2 – 35 ≥ –12.5 c2 ≥ 22.5

Since c2 = 35 + ∆; ∆ = c2 – 35. Thus

Summarizing, 35 ≤ c2 ≤ 45.

c2 – 35 ≥ 0 c2 ≥ 35 –5 + ∆/2 ≤ 0 ∆/2 ≤ 5 ∆ ≤ 10

e) q4:

Since c2 = 35 + ∆; ∆ = c2 – 35. Thus c2 – 35 ≤ 10 c2 ≤ 45 –25 – 2∆ ≤ 0 –2∆ ≤ 25 ∆ ≥ –12.5

s1:

10 – 4∆ ≥ 0 –4∆ ≥ –10 ∆ ≤ 5/2

s2:

60 – 5∆ ≥ 0 –5∆ ≥ –60 ∆ ≤ 12

x3:

10 – ∆ ≥ 10 –∆ ≥ –10 ∆ ≤ 10

x2:

30 + 2∆ ≥ 0 2∆ ≥ –30 ∆ ≥ –15

Therefore, –15 ≤ ∆ ≤ 5/2. Since q4 = 40 + ∆ ∆ = q4 – 40 –15 ≤ q4 – 40 ≤ 5/2 25 ≤ q4 ≤ 42.5

f) The marginal value of 1 ft2 of storage is $25. From part e, the sensitivity range for q4 is 25 ≤ q4 ≤ 42.5. Thus, the company would purchase up to 42.5 ft2 of storage space at the marginal value price. 49. a) Maximize Zd = 20y1 + 30y2 + 12y3 subject to 4y1 + 12y2 + 3y3 ≤ .03 5y1 + 3y2 + 2y3 ≤ .02 y1, y2, y3 ≥ 0 b) y1 = $0 = marginal value of 1 mg of protein; y2 = $0 = marginal value of 1 mg of iron; y3 = $.01 = marginal value of 1 mg of carbohydrate (i.e., if one less mg of carbohydrate was required, it would be worth $.01 to the dietitian)

309


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c) c1, basic: cj

Basic Variables

.03 + ∆

.02

0

0

0

Quantity

x1

x2

s1

s2

s3

.02

x2

3.6

0

1

0

.20

–.80

.03 + ∆

x1

1.6

1

0

0

–.13

.20

s1

4.4

0

0

1

.47

–3.2

zj

.12 + 1.6∆

.02

0

0 – .133∆ –.01 + .2∆

0

0

0 – .133∆ –.01 + .2∆

0

.03 + ∆

zj – cj

0

Since c2 = .02 + ∆; ∆ = c1 – .02. Thus

Solving for the zj – cj inequalities: 0 – .133∆ ≤ 0 –.133∆ ≤ 0 –∆ ≤ 0 ∆≥0

c2 – .02 ≤ 0 c2 ≤ .02 –.01 + .8∆ ≤ 0 .8∆ ≤ .01 ∆ ≤ .0125

Since c1 = .03 + ∆; ∆ = c1 – .03. Thus

Since c2 = .02 + ∆; ∆ = c1 – .02. Thus

c1 – .03 ≥ 0 c1 ≥ .03 –.01 + .2∆ ≤ 0 .2∆ ≤ .01 ∆ ≤ .05

c2 – .02 ≤ .0125 c2 ≥ .0075 Summarizing, c2 ≤ .0375. d) When determining sensitivity ranges for qi values in a minimization problem, since artificial variables are eliminated, the surplus variable column coefficients must be used. This corresponds to a qi – ∆ change.

Since c1 = .03 + ∆; ∆ = c1 – .03. Thus c1 – .03 ≤ .05 c1 ≤ .08 Summarizing, .03 ≤ c1 ≤ .08. c2, basic:

cj

Basic Variables

.03

.02 + ∆

0

0

0

Quantity

x1

x2

s1

s2

s3

.02 + ∆

x2

3.6

0

1

0

.20

–.80

.03

x1

1.6

1

0

0

–.13

.20

0

s1

4.4

0

0

1

.47

–3.2

zj

.12 + 3.6∆

zj – cj

.03 0

.02 + ∆ 0

0

0 + .2∆

–.01 + .8∆

0

0 + .2∆

–.01 + .8∆

Solving for the zj – cj inequalities: 0 + .2∆ ≤ 0 .2∆ ≤ 0 ∆≤0

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q1: x2:

3.6 + 0∆ ≥ 0

x1:

1.6 + 0∆ ≥ 0

s1:

Therefore, ∆ ≥ –4.4. Since q1 = 20 – ∆ ∆ = 20 – q1 20 – q1 ≥ –4.4 q1 ≤ 24.4 q2: x2:

s1:

3.6 + .2∆ ≥ 0 x1: 1.6 – .133∆ ≥ 0 .2∆ ≥ –3.6 –.133∆ ≥ –1.6 ∆ ≥ –18 –∆ ≥ –12 ∆ ≤ 12 4.4 + .47∆ ≥ 0 .47∆ ≥ –4.4 ∆ ≥ –9.36

Therefore, –9.36 ≤ ∆ ≤ 12. Since q2 = 30 – ∆ ∆ = 30 – q2 –9.36 ≤ 30 – q2 ≤ 12 18 ≤ q2 ≤ 39.36 q3: x2:

s1:

3.6 – .8∆ ≥ 0 x1: –.8∆ ≥ –3.6 –∆ ≥ –4.5 ∆ ≤ 4.5

1.6 + .2∆ ≥ 0 .2∆ ≥ –1.6 ∆ ≥ –8

4.4 – 3.2∆ ≥ 0 –3.2∆ ≥ –4.4 –∆ ≥ –1.375 ∆ ≤ –1.375

Therefore, –8 ≤ ∆ ≤ 1.375. Since q3 = 12 – ∆ ∆ = 12 – q3 –8 ≤ 12 – q3 ≤ 1.375 10.625 ≤ q3 ≤ 20 e) The marginal value of 1 mg of carbohydrates is $.01. From part d, the sensitivity range for q3, carbohydrates, is 10.625 ≤ q3 ≤ 20. Thus, the dietitian could lower the requirements for carbohydrates to10.625 at the marginal value without the solution becoming infeasible.

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50. a) Minimize Zd = 1,200y1 + 500y3 subject to .50y1 + y2 ≥ 1.25 1.2y1 – y2 + y3 ≥ 2.00 .80y1 + y2 ≥ 1.75 y1, y2, y3 ≥ 0 y1 = the marginal value of an additional hour of production time = $0 y2 = the marginal value of increasing the combined demand for cheese sandwiches by one sandwich = $1.75 y3 = the marginal value of producing an additional ham salad sandwich = $3.75 b) c1, non-basic: –5 + ∆ ≤ 0 ∆ ≤ .50 Since c1 = 1.25 + ∆; ∆ = c1 – 1.25. Therefore, c1 – 1.25 ≤ .50 c1 ≤ 1.75 c2, basic: –3.75 – ∆ ≤ 0 –∆ ≤ 3.75 ∆ ≥ –3.75 Since c2 = 2 + ∆; ∆ = c2 – 2. Therefore, c2 –2 ≥ –3.75 c2 ≥ –1.75 c3, basic: –.5 – ∆ ≤ 0 –∆ ≤ .5 ∆ ≥ –.5

–3.75 – ∆ ≤ 0 –∆ ≤ 3.75 ∆ ≥ –3.75

Summarizing, –3.75 ≤ –.5 ≤ ∆ and, therefore, –.5 ≤ ∆ Since c3 = 1.75 + ∆; ∆ = c3 – 1.75. Therefore, –.5 ≤ ∆ –.5 ≤ c3 – 1.75 1.25 ≤ c3

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c) q3: s1:

200 – 2∆ ≥ 0 x3: –2∆ ≥ –200 ∆ ≤ 100

500 + ∆ ≥ 0 x2: ∆ ≥ –500

500 + ∆ ≥ 0 ∆ ≥ –500

Summarizing, –500 ≤ ∆ ≤ 100 Since q3 = 500 + ∆, ∆ = q3 – 500. Therefore, –500 ≤ q3 – 500 ≤ 100 0 ≤ q3 ≤ 600 d) The marginal value for demand for cheese sandwiches is $1.75. The range for q2 is computed as follows. s1:

200 – .8∆ ≥ 0 x3: –.8∆ ≥ –200 ∆ ≤ 250

500 + ∆ ≥ 0 x2: ∆ ≥ –500

Summarizing, –500 ≤ ∆ ≤ 250 Since q2 = 0 + ∆, ∆ = q2. Therefore, –500 ≤ q2 ≤ 250 Thus, the demand for cheese sandwiches can be increased up to a maximum of 250 sandwiches.

The additional profit for 200 more cheese sandwiches would be, ($1.75) (200) = $350 Since the cost of advertising is $100, a $250 profit would result, therefore the company should advertise.

51. a) c3, nonbasic: –13 – ∆ ≤ 0 –∆ ≤ 13 ∆ ≥ –13 Since c3 = 2 + ∆, ∆ = c3 – 2. And c3 – 2 ≥ –13 c3 ≥ –11

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500 + 0∆ ≥ 0 0∆ ≥ –500 ∆≤∞


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c1, basic: cj

Basic Variables

3+∆

5

2

0

0

0

Quantity

x1

x2

x3

s1

s2

s3

0

s2

15

0

0

–4

–3/2

1

–1/2

3+∆

x1

5

1

0

–2

–1/2

0

1/2

5

x2

30

0

1

–1

–1/2

0

–1/2

zj

165 + 5∆

3+∆

5

–11 – 2∆

–4 – ∆/2

0

–1 + ∆/2

0

0

–13 – 2∆

–4 – ∆/2

0

–1 + ∆/2

zj – cj

Solving for the zj – cj inequalities:

Solving for the zj – cj inequalities:

–13 – 2∆ ≤ 0 –2∆ ≤ 13 ∆ ≥ –13/2

–13 – 2∆ ≤ 0 –2∆ ≤ 13 ∆ ≥ –13/2

Since c1 = 3 + ∆, ∆ = c1 – 3. Thus

Since c2 = 5 + ∆, ∆ = c2 – 5. Thus

c1 – 3 ≥ –13/2 c1 ≥ –7/2 –4 – 2∆ ≤ 0 –2∆ ≤ 4 ∆ ≥ –2

c2 – 5 ≥ –13/2 c2 ≥ –3/2 –4 – ∆/2 ≤ 0 –∆/2 ≤ 4 ∆ ≥ –8

Since c1 = 3 + ∆, ∆ = c1 – 3. Thus

Since c2 = 5 + ∆, ∆ = c2 – 5. Thus

c1 – 3 ≥ –2 c1 ≥ 1 –1 + ∆/2 ≤ 0 ∆/2 ≤ 1 ∆≤2

c2 – 3 ≥ –8 c2 ≥ –3 –1 – ∆/2 ≤ 0 –∆/2 ≤ 1 ∆ ≥ –2

Since c1 = 3 + ∆, ∆ = c1 – 3. Thus

Since c2 = 5 + ∆, ∆ = c2 – 5. Thus

c1 – 3 ≤ 2 c1 ≤ 5

c2 – 5 ≥ –2 c2 ≥ 3

Summarizing, 1 ≤ c1 ≤ 5.

Summarizing, c2 > 3.

c2: basic:

cj

Basic Variables

3

5+∆

2

0

0

0

Quantity

x1

x2

x3

s1

s2

s3

0

s2

15

0

0

–4

–3/2

1

–1/2

3

x1

5

1

0

–2

–1/2

0

1/2

5+∆

x2

30

0

1

–1

–1/2

0

–1/2

zj

165 + 30∆

3

5+∆

–11 – 2∆

–4 – ∆/2

0

–1 – ∆/2

0

0

–13 – 2∆

–4 – ∆/2

0

–1 – ∆/2

zj – cj

314


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b) When determining sensitivity ranges for qi values, since artificial values are eliminated, the surplus variable column coefficients must be used. This corresponds to a qi – ∆ change. q1: s2:

15 – 3∆/2 ≥ 0 –3∆/2 ≥ –15 ∆ ≤ 10

x1:

5 – ∆/2 ≥ 0 –∆/2 ≥ –5 ∆ ≤ 10

x2:

30 – ∆/2 ≥ 0 –∆/2 ≥ –30 ∆ ≤ 60

x1:

5 – 0∆ ≥ 0

x2:

30 – 0∆ ≥ 0

x1:

5 + ∆/2 ≥ 0 ∆/2 ≥ –5 ∆ ≥ –10

x2:

30 – ∆/2 ≥ 0 –∆/2 ≥ –30 ∆ ≤ 60

Therefore, ∆ ≤ 10. Since q1 = 35 – ∆ ∆ = 35 – q1 35 – q1 ≤ 10 q1 ≥ 25 q2: s2:

15 + ∆ ≥ 0 ∆ ≥ –15

Therefore, ∆ ≤ –15. Since q2 = 50 – ∆ ∆ = 50 – q2 50 – q2 ≤ –15 q2 ≤ 65 q3: s2:

15 – ∆/2 ≥ 0 –∆/2 ≥ –15 ∆ ≤ 30

Therefore, –10 ≤ ∆ ≤ 30. Since q3 = 25 – ∆ and ∆ = 25 – q3 –10 ≤ 25 – q3 ≤ 30 –5 ≤ q3 ≤ 35

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52. a) y1 = 7/15 = $.467

d) Range for q5:

Range for q1:

s5:

x1: 8 + ∆/15 ≥ 0 x2: 16 – ∆/30 ≥ 0 ∆/15 ≥ –8 –∆/30 ≥ –16 ∆ ≥ –120 ∆ ≤ 480

Since q5 = 40 + ∆, ∆ = q5 – 40 q5 – 40 ≥ –8 q5 ≥ 32

x3: 3 – ∆/40 ≥ 0 ∆ ≥ 120 s4: 36 – ∆/30 ≥ 0 –∆/30 ≥ – 36 ∆ ≤ 1,080

s5: 8 – ∆/10 ≥ 0 –∆/10 ≥ –8 ∆ ≤ 80 –120 ≤ ∆ ≤ 80

No, increasing q5 from 40 to 50 will have no affect on the optimal solution. e) Since y1 = 7/15 = $.467, pears should be secured.

Since q1 = 320 + ∆,

53. a) y2 = $0, spruce has no marginal value

∆ = q1 – 320 –120 ≥ q1 – 320 ≤ 80 200 ≤ q1 ≤ 400

q2: s2:

As many as 400 pears can be purchased.

∆ = q2 – 160 q2 – 160 ≥ –70 q2 ≥ 90

Range for q2: 8 + ∆/30 ≥ 0 x2: 16 + ∆/15 ≥ 0 ∆/30 ≥ –8 ∆/15 ≥ –16 ∆ ≥ –240 ∆ ≥ –240

3 – ∆/10 ≥ 0 –∆/10 ≥ –3 ∆ ≤ 30 –240 ≤ ∆ ≤ 30 x3:

b) y3 = $2, marginal value of cutting hours q3:

s4: 36 – ∆/30 ≥ 0 –∆/30 ≥ –36 ∆ ≤ 1,080

Since q2 = 400 + ∆, ∆ = q2 – 400 –240 ≤ q2 – 400 ≤ 30 160 ≤ q2 ≤ 430

s1: 80 – 4∆/3 ≥ 0 s2: –4∆/3 ≥ –80 ∆ ≤ 60

70 + ∆/3 ≥ 0 ∆/3 ≥ –70 ∆ ≥ –210

x3: 20 + 2∆/3 ≥ 0 x2: 2∆/3 ≥ –20 ∆ ≥ –30

10 – ∆/3 ≥ 0 –∆/3 ≥ –10 ∆ ≤ 30

Therefore, –30 ≤ ∆ ≤ 30. Since q3 = 50 + ∆, ∆ = q3 – 50 20 ≤ q3 ≤ 80

Range over which the value of peaches is valid c) Range for q3: s3:

70 + ∆ ≥ 0 ∆ ≥ –70

Since q2 = 160 + ∆,

b) y2 = 1/15 = $.067

x1:

8+∆≥0 ∆ ≥ –8

c) y3 = $2, cutting hours; y4 = $2, pressing hours. Since they both have the same marginal value, management could choose either.

3+∆≥0 ∆ ≥ –3

Since q3 = 43 + ∆, ∆ = q3 – 43 q3 – 43 ≥ –3 q3 ≥ 40 No, increasing q3 from 43 to 60 will not affect the optimal solution.

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d) From part a, q2 ≥ 90; thus, a decrease from 160 to 100 lb of spruce will not affect the solution. e) Compute the range for c1, a nonbasic cj value. c1 = 4 + ∆ –2 + ∆ ≤ 0 ∆≤2 c1 – 4 ≤ 2 c1 ≤ 6 The unit profit from Western paneling would have to be $6 or more before it would be produced. f) Compute the range for c3. c3 = 8 + ∆ –2 – ∆/3 ≤ 0 –2 – 2∆/3 ≤ 0 –∆/3 ≤ 2 –2∆/3 ≤ 2 ∆ ≥ –6 ∆ ≥ –3

–2 +∆/6 ≤ 0 ∆/6 ≤ 2 ∆ ≤ 12

Since ∆ = c3 – 8, c3 – 8 ≥ –6 c3 ≥ 2

c3 – 8 ≥ –3 c3 ≥ 5

c3 – 8 ≤ 12 c3 ≤ 20

Summarizing, 5 ≤ c3 ≤ 20. If the unit profit of Colonial paneling is increased to $13, the percent solution would not be affected. 54.

y1 = $1.33 q1: x4: 80 + 2∆/3 ≥ 0 x2: 2∆/3 ≥ –80 ∆ ≥ –120

40 – ∆/3 ≥ 0 –∆/3 ≥ –40 ∆ ≤ 120

–120 ≤ ∆ ≤ 120 Since q1 = 200 + ∆, ∆ = q1 – 200 –120 ≤ q1 – 200 ≤ 120 80 ≤ q1 ≤ 320

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