Question

A project consists of three parallel paths with mean durations and variances of (10,4), (12,4) and (12,9) respectively. According to the standard pert assumptions, the distribution of the project duration is

Answer 1

Answer:

Beta distribution with mean 12 and standard deviation 2

Step-by-step explanation:

In PERT analysis, a Beta distribution is assumed.

In the question, the three parallel paths are given.

The critical path will be the one with the longest time duration.

Two paths have same time duration of 12.

Therefore, mean duration = 12

The Standard Deviation = $]\SQRT{4}$ = $2$

Therefore, the distribution of the project duration is beta distribution with mean 12 and standard deviation 2.

Hope this helps.

Answer 2

Answer:d

Step-by-step explanation:

Longest path is the critical path, therefore mean is 12.

If two longest paths having same completion time, than highest variance will decide project completion time, therefore S.D=sqrt(9)=3

Project duration is a Normal distribution.

(Where as, activity is a Beta distribution)