You are the project manager for your organization. You have recorded the following duration estimates for an activity in your project: optimistic 20, most likely 45, pessimistic 90. What time will you record for this activity?
Correct Answer: A
Explanation/Reference:
Explanation:
This is an example of a three-point estimate. A three-point estimate records the optimistic, most likely, and the pessimistic duration, and then records an average for the predicted duration Three-point estimate is a way to enhance the accuracy of activity duration estimates. This concept is originated with the Program Evaluation and Review Technique (PERT). PERT charts the following three estimates: Most likely (TM):
The duration of activity based on realistic factors such as resources assigned, interruptions, etc.
Optimistic (TO): The activity duration based on the best-case scenario
Pessimistic (TP): The activity duration based on the worst-case scenario The expected (TE) activity duration is a weighted average of these three estimates:
TE = (TO + 4TM + TP) / 6
Duration estimates based on the above equations (sometimes simple average of the three estimates is also used) provide more accuracy. It can be calculated as follows:
TE = ( 20 + 45*4 + 90) / 6
= 290/6
=48
Incorrect Answers:
B, C, D: These are not the valid answers for this question.