Problem
The table below gives the activity duration and precedence relationships for a small project consisting of six activities. Also shown is the cost per day of crashing each activity and the maximum number of days that each activity may be crashed.
|
Activity
|
Predecessor
|
Normal Time (days)
|
Maximum Crashing (days)
|
$/day
|
|
1
|
_
|
9
|
5
|
5000
|
|
2
|
_
|
7
|
3
|
6000
|
|
3
|
1
|
5
|
3
|
4000
|
|
4
|
1,2
|
8
|
4
|
2000
|
|
5
|
3
|
6
|
3
|
3000
|
|
6
|
4,5
|
9
|
5
|
9000
|
(1) Determine which activities should be crashed, and by how much, to complete the project in 22 days.
(2) Suppose there is no specific completion time but that there is a payment of $5000 for each day that the project duration is reduced below the normal completion time.
Determine the optimum number of days to complete the project and which activities would be crashed and by how many days.