PMP Practice Questions #111
You are managing a project to develop a new software tool. For one of the critical tasks, the software development, your team has provided the following estimates based on their expertise and analysis of similar tasks in past projects:
Optimistic time (O): 90 days
Most likely time (M): 120 days
Pessimistic time (P): 180 days
Using the PERT technique, what is the expected time (TE) for the software development task?
A) 120 days
B) 130 days
C) 125 days
D) 135 days
Analysis:
When managing a project to develop a new software tool, employing the Program Evaluation and Review Technique (PERT) for estimating the duration of critical tasks is a strategic approach. This technique leverages three types of estimates to forecast a task’s expected duration: the optimistic time (O), the most likely time (M), and the pessimistic time (P). These estimates are derived from the team’s expertise and historical data from similar projects, offering a balanced view of potential outcomes.
The PERT formula used is TE=(O+4M+P) / 6 where TE represents the expected time. This calculation accounts for uncertainties inherent in project tasks by providing a weighted average that emphasizes the most likely outcome while considering the best and worst scenarios. It’s a valuable tool for project schedule management, enabling project managers to plan more effectively and anticipate potential delays.
Analysis of Options:
Option A: 120 days. This option represents the most likely time estimate provided by the team, not the expected time calculated using the PERT formula.
Option B: 130 days. This option does not correspond with the PERT calculation result for the expected time, based on the given estimates.
Option C: 125 days. Correctly applies the PERT formula: (90+4×120+180)/6, yielding an expected time of 125 days for the software development task. This reflects a weighted average, giving more emphasis to the most likely outcome while considering the best and worst scenarios.
Option D: 135 days. Like Option B, this does not align with the PERT calculation and exceeds the provided time estimates.
Conclusion: The most accurate approach to determining the expected time for the software development task, using the PERT technique with the provided estimates, is Option C 125 days. This method effectively combines the optimistic, most likely, and pessimistic times to forecast a realistic expected duration, accounting for uncertainties inherent in project tasks. It is a valuable tool in project schedule management, enabling project managers to plan more effectively and anticipate potential delays.
PMP Exam Content Outline Mapping
| Domain | Task |
|---|---|
| Process | Task 6: Plan and manage schedule |
Topics Covered
- Three Point Estimation
- PERT Technique
