Operations and Supply Chain Management The Core

ANSWERS TO SELECTED OBJECTIVE QUESTIONS appendix B 505
21. Least total cost order 180 to cover periods
4 through 8. Least unit cost is tied for ordering
180 for periods 4 through 8, or order 220 units
to cover 4 through 9, therefore either 180 or
220 units in period 2.
Chapter 10
9. DPMO = 15,333; this is not very good.
14. Opportunity flow diagram.
17. a. Cost when not inspecting = $20/hr, cost to
inspect = $9/hr, therefore inspect; b. $0.18
each; c. $0.22 per unit.
22. a. .333; b. No, the machine is not capable of a
high enough quality.
25. UCL = 1014.965, LCL = 983.235 for X-bar
chart; UCL = 49.552, LCL = 0.00 for the
R-chart.
Chapter 11
4. Purchase 268 boxes of lettuce.
14. q = 713
17. a. Q = 1,225, R = 824; b. q = 390 − I
Chapter 12
10. 5 kanban card sets
14. 5 kanban card sets
Chapter 13
11. Buy NPV = $143,226.27, make NPV =
$84,442.11, we should accept the bid.
16. Inventory turn = 148.6, weeks of supply =
.350 (1/3 of a week’s supply on-hand)
Chapter 14
9. Total cost $1,056.770; b. Should consider
closing the Philadelphia plant since we
are using very little of the capacity from
that plant.
10. C x = 373.8, C y = 356.9
Appendix A
2. Optimal combination is B = 10, A = 15,
and Z = 70
4. a. 600A + 900B <= 3,600
600A + 900B >= 1,800
200A + 700B <= 1,400
400A + 100B >= 400
A <= 2
Minimize .75A + .15B
b. A = 0.54
B = 1.85
Obj = 0.68