Question

Given the following information, compute the early, late, and slack times for the project network. Which activities on the critical path have only the start or finish of the activity on the critical path?

Answer 1

Network Diagram is prepared using Handwritten Format, here, I have used forward and backward path Method,

Important Formula:

Early start of an activity = Highest Early finish time among all predecessor activities

Late finish of an activity = Lowest Late start time among all successor activities,

Slack = Late start - Early Start = late Finish - Early finish

Early finish = Early start + Duration

Late start = Late finish - Duration

From the below network diagram, critical path is Start - A-B-D-E-F-G-H-J-End,

as activities on that path have zero slack time, project needs 38 unit time to complete,

Early finish of predecessor activity+ Lag time = Early start of an activity

Late finish of an Activity = Late start of an successor activity - Lag time,

ES,EF, LS, LF and Slack data for each activity are shown in the below network diagram,