HKSM

A task that lies on the project's critical path, meaning its timing directly sets the earliest possible project completion; any delay to it delays the overall finish date.

Key Points

• Part of the sequence that determines the project's minimum duration (the critical path).
• Typically has zero total float; a slip here pushes the project end date.
• Crashing or fast-tracking these tasks can shorten the overall schedule but may increase cost or risk.
• The set of critical activities can change as durations, resources, or dependencies change.

Example

In a construction project, the path A (3 days) - B (7 days) - C (10 days) totals 20 days, while a parallel path D (5 days) - E (8 days) totals 13 days. Activities A, B, and C are critical path activities. If B finishes 2 days late and nothing else changes, the project completion also moves 2 days later.

PMP Example Question

Which statement best describes a critical path activity?

1. An activity with zero total float whose delay will delay the project completion date.
2. An activity chosen because it is the most expensive work in the project.
3. An activity that can slip without affecting any successor or the finish date.
4. An activity that is not on the longest path but still uses the most resources.

Correct Answer: A — a task on the critical path (zero total float)

Explanation: Critical path activities govern the project's minimum duration; any delay to them directly delays the project's finish.