1. Crashing – Shortening an activity
Crash time – The shortest possible time an activity can realistically be
completed in
Crash cost – The direct cost for completing an activity in its crash time
Project Compression / Crashing
2. Normal Crashed
Activity Duration Cost Duration Cost
A 5 $ 1,000 3 $ 5,000
B 7 $ 2,000 4 $ 6,000
C 9 $ 3,000 5 $ 7,000
D 11 $ 4,000 6 $ 10,000
Given the cost information in the table, what is the cheapest activity to
crash on a per week basis
3. The cost per unit of time or slope for any activity is computed
by the following equation
Cost Slope = (Crash Cost – Normal Cost) / (Normal Time – Crash Time)
4. Normal Crashed
Activity Duration Cost Duration Cost
A 5 $ 1,000 3 $ 5,000
B 7 $ 2,000 4 $ 6,000
C 9 $ 3,000 5 $ 7,000
D 11 $ 4,000 6 $ 10,000
5. Normal Crashed
Activity Duration Cost Duration Cost Slope
A 5 $ 1,000 3 $ 5,000 $ 2,000
B 7 $ 2,000 4 $ 6,000 $ 1,333.33
C 9 $ 3,000 5 $ 7,000 $ 1,000
D 11 $ 4,000 6 $ 10,000 $ 1,200
What is the cheapest activity to crash on a per week basis ?
Activity C