All five members of a project team add 20% to their individual serial activities as a safety margin and submit their time estimates to the project manager.The manager adds the activity length estimates together and adds 20% for his personal safety margin.Then,anticipating a cut by top management,he adds another 20% to his final project estimate.Much to his surprise,top management cuts only 10% off his time estimate.How much of a cushion is now built into the project?
A)62%
B)74%
C)56%
D)42%

Question

Quizplus · Accepted Answer

The total safety margin added by the team is 20% * 5 = 100%
Adding this to the individual activity length estimates, we get a total estimate with 100% safety margin.
The project manager then adds another 20%, making the total estimate with 120% safety margin.
Top management cuts only 10% of this total estimate, which means the remaining cushion is 90% of the 120% estimate.
90% of 120% = 108%, which means there is a cushion of 108% - 100% = 8% built into the project.
Therefore, the correct answer is C) 56%.

All Five Members of a Project Team Add 20% to Their