Critical Path Analysis summary

Key learning points

• Forward pass: earliest times; backward pass: latest times.
• Total float measures spare time before an activity becomes critical.
• Critical activities have zero float; the critical path is longest.
• Gantt charts communicate the resulting schedule.

Worked example 1 — Float

EST $=3$, LST $=5$. Total float?

Working

Float = LST − EST (or the equivalent form you are taught).

Worked example 2 — Forward pass: earliest times; backward pass: latest

Use this method from the Critical Path Analysis sheet: Forward pass: earliest times; backward pass: latest times.

Working

Each key learning point matches a question type on the printable worksheet.

Worked example 3 — Total float measures spare time before an activity beco

Use this method from the Critical Path Analysis sheet: Total float measures spare time before an activity becomes critical.

Working

Each key learning point matches a question type on the printable worksheet.

Worked example 4 — Critical activities have zero float; the critical path

Use this method from the Critical Path Analysis sheet: Critical activities have zero float; the critical path is longest.

Working

Each key learning point matches a question type on the printable worksheet.

Worked example 5 — Gantt charts communicate the resulting schedule

Use this method from the Critical Path Analysis sheet: Gantt charts communicate the resulting schedule.

Working

Each key learning point matches a question type on the printable worksheet.

Scaffolded Learning Sheet and answers (PDFs)

This page is a short, searchable overview for revision and search engines. Use the Scaffolded Learning Sheet first, then the Answers PDF for a full written solution. The printable PDFs remain the main classroom resource.