Critical Path Method Flashcards
7 cards from real Project Management practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Critical Path Method flashcards as text
In CPM, what does 'free float' (free slack) represent?
Answer: The amount of time an activity can be delayed without delaying any successor activity's early start
Free float is the amount of time an activity can be delayed without affecting the early start of any immediate successor.
A project network has Activity A (3 days) → Activity C (4 days) and Activity B (5 days) → Activity C. What is the earliest Activity C can start if both A and B start on Day 1?
Answer: Day 6
Activity C can start only after both predecessors finish: A ends Day 4, B ends Day 6, so C starts Day 6 (using 0-based indexing where Day 1 = start).
Which scheduling technique uses a single time estimate per activity, unlike PERT which uses three?
Answer: Critical Path Method (CPM)
CPM uses a single deterministic time estimate per activity, while PERT uses optimistic, most likely, and pessimistic estimates.
If the project completion date is moved earlier by management, what is the effect on the critical path?
Answer: Some previously non-critical activities may become critical
Compressing the required end date reduces total float across the network, potentially making previously non-critical paths critical.
What is 'negative float' in a project schedule?
Answer: An indicator that the project cannot be completed by the required date without intervention
Negative float means an activity's late finish is earlier than its early finish, indicating the schedule is infeasible without corrective action.
During a backward pass in CPM, how is the Late Start (LS) of an activity calculated?
Answer: LS = Late Finish - Duration
Late Start is calculated as Late Finish minus the activity's duration, working backwards through the network.
What scheduling constraint creates a 'Start-to-Finish' (SF) dependency between two activities?
Answer: Activity B cannot finish until Activity A starts
In a Start-to-Finish dependency, the successor (B) cannot finish until the predecessor (A) has started — the rarest of the four dependency types.