Chapter 3, Problem 10DQ

Summary Introduction

To determine: How the times and variances of an expected activity can be computed in a PERT network.

Introduction:

The activity times of various tasks in a PERT project network are assumed to follow a probability distribution.

For calculating the expected times and variances, the following are the parameters required:

• Optimistic time: This is the time denoted by “a”, which is the best possible or in other words, the quickest time in which an activity can be completed, assuming that everything goes as per plan.
• Pessimistic time: This is the worst case scenario, where all the conditions are adverse or unfavorable. The maximum time which may be taken in such a situation is the pessimistic time denoted by “b”.
• Most likely time: The most realistic estimate of the time, denoted by “m” in normal conditions, is another parameter which is important in the computation of expected times and variances.