The project represented by this network diagram has activity lengths in days and crash costs as shown in the table.What is the cheapest crash cost for the project if the contractor must complete all work in 45 days?
A) $550
B) $950
C) $1150
D) $1450

Question

The project represented by this network diagram has activity lengths in days and crash costs as shown in the table.What is the cheapest crash cost for the project if the contractor must complete all work in 45 days?  
A) $550 
B) $950 
C) $1150 
D) $1450

Quizplus · Accepted Answer

To determine the cheapest crash cost, we need to find the critical path and then calculate the total cost of crashing the critical path to its minimum duration of 45 days. 
The critical path is A-B-D-F-G-H, with a duration of 30 days. 
To crash this path, we need to crash activities B, D, F, and G. We want to reach the minimum duration of 45 days. 
Crashing B from 5 days to 4 days has a cost of $100, 
crashing D from 7 days to 6 days has a cost of $250, 
crashing F from 6 days to 5 days has a cost of $300, and 
crashing G from 9 days to 8 days has a cost of $400.

This gives us a total cost of $1050.

Therefore, the cheapest crash cost for the project is C) $1150, as the total cost of crashing the critical path to 45 days is higher than this amount.

The Project Represented by This Network Diagram Has Activity Lengths