What is the late start (LS) of activity C?

What is the late start (LS) of activity C?

• A. 6 days
• B. 10 days
• C. 12 days
• D. 8 days

Answer: (D)

Late start is the latest moment you can begin an activity without delaying the project finish. You find it by performing a backward pass through the network: determine the latest finish times for activities (often starting from the project completion) and then compute each activity’s LS as LS = LF − duration. For activity C, the constraints from its successors and the project finish line up to give an LS of 8 days. In other words, you must start C by day 8 to keep the schedule intact; starting later would push the overall finish date. The other values would require different latest finish times or durations and would not fit the network constraints.

Late start is the latest moment you can begin an activity without delaying the project finish. You find it by performing a backward pass through the network: determine the latest finish times for activities (often starting from the project completion) and then compute each activity’s LS as LS = LF − duration. For activity C, the constraints from its successors and the project finish line up to give an LS of 8 days. In other words, you must start C by day 8 to keep the schedule intact; starting later would push the overall finish date. The other values would require different latest finish times or durations and would not fit the network constraints.