Operations Management - Use critical path for how long total process will take

92 section 1 OPERATIONS STRATEGY AND MANAGING CHANGE



If you will save $1,000 for each day that the earliest completion time is reduced, whi
action, if any, would you choose?
e. What is the probability that the project will take more than 30 days to complete?
8 Here is a network with the activity times shown in days:




a. Find the critical path.
b. The following table shows the normal times and the crash times, along with the associat
costs for each activity.
ACTIVITY NORMAL TIME CRASH TIME NORMAL COST CRASH COST


A 7 6 $7,000 $ 8,000
B 3 2 5,000 7,000
C 4 3 9,000 10,200
D 5 4 3,000 4,500
E 2 1 2,000 3,000
F 4 2 4,000 7,000
G 5 4 5,000 8,000


If the project is to be shortened by four days, show which activities, in order of reductio
would be shortened and the resulting cost.
9 The home office billing department of a chain of department stores prepares monthly inve
tory reports for use by the stores' purchasing agents. Given the following information, use d
critical path method to determine
a. How long the total process will take.
b. Which jobs can be delayed without delaying the early start of any subsequent activity.
IMMEDIATE TIME
JOB AND DESCRIPTION PREDECESSORS (HOURS)
-
a Start 0
b Get computer printouts of customer purchases a 10
c Get stock records for the month a 20
d Reconcile purchase printouts and stock records b, c 30
. ,
,.
1 e Total stock records by department b, c 20
. f
..
.
.~ Determine reorder quantities for coming period e 40

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!
g
h
Prepare stock reports for purchasing agents
Finish
d, f
g
20
0


C~ 10 For the network shown:

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