# PMP Exam Question 122

## Triangular distribution :

You are estimating activity durations in the project you manage. You estimate 43 days as the most likely duration of an activity. In a best-case scenario, the activity will last 37 days and 55 days in the worst-case scenario. Based on triangular distribution, what is the estimated duration of that activity?

A. 36 days.
B. 41 days.
C. 44 days.
D. 45 days.

### 1 responses on "PMP Exam Question 122"

1. PMP Solution 122

C. If the question had asked for the estimated duration based on beta distribution, that choice would have been the right answer; cE = (cO + 4cM + cP) / 6; cE = (37 + (4 x 43) + 55) / 6 = 44 days. However, the question is focused on triangular distribution estimate..

The accuracy of single-point duration estimates may be improved by considering estimation uncertain-ty and risk. Using three-point estimates helps define an approximate range for an activity’s duration. Triangular distribution is used when there is insufficient historical data or when using judgmental data;
Triangular distribution formula. tE = (tO + tM + tP) / 3; tE = (37 + 43 + 55) / 3 = 45 days
Therefore, right answer is D. [PMBOK 6th edition, Page 201] [Project Schedule Management]

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