A project represented by the activities shown in this table must meet a deadline of 51 days. Sketch the network and determine the critical path

Question

Using the crash costs and minimum activity lengths shown in the table, determine which activities to shorten and provide the total cost of finishing this project in 51 days.

Activity Predecessor Normal Duration (days) Crash Duration (days) Crash Cost ($/day)
A -- 14 12 485
B A 5 4 775
C B, D 7 6 460
D A 16 12 670
E D 18 13 50
F C, E, G 19 14 265
G A 18 16 400
What will be an ideal response?

Answer 1

Answer: Initially, path lengths are ABCF = 45, ADCF = 56, ADEF = 67, and AGF = 51.
Purchases made in increasing order of cost per day are as follows:
Reduce E from 18 to 13 days for 5($50) = $250; ADEF = 62 days
Reduce F from 19 to 14 days for 5($265) = $1325; ADEF = 57 days
Reduce A from 14 to 12 days for 2($485) = $970; ADEF = 55 days
Reduce D from 16 to 12 days for 4($670) = $2680; ADEF = 51 days
Paths are now: ABCF = 38; ADCF = 44; ADEF = 51; AGF = 44
Total crash cost is $250 + $1325 + $970 + $2680 = $5225