CST Critical Path & Float Analysis 2

Question 1

A project activity has an Early Start of day 10, Late Start of day 15, Early Finish of day 20, and Late Finish of day 25. What is the Total Float?

Accepted Answer

5 days

Answer

Total Float = Late Start − Early Start (or Late Finish − Early Finish) = 15 − 10 = 5 days.

Question 2

Which of the following best describes Free Float?

Accepted Answer

The amount of time an activity can be delayed without delaying the Early Start of any successor

Answer

Free Float is the amount of time an activity can be delayed without affecting the Early Start of any immediate successor.

Question 3

On a network diagram, Activity A (duration 4) → Activity B (duration 3) → Activity C (duration 5). Activity A also connects to Activity D (duration 6) → Activity C. Which path is critical?

Accepted Answer

A → D → C with duration 15

Answer

Path A→D→C = 4+6+5 = 15 days; Path A→B→C = 4+3+5 = 12 days; the longest path (15 days) is the critical path.

Question 4

An activity on the critical path has its duration increased by 3 days. What is the effect on the project?

Accepted Answer

Project duration increases by 3 days

Answer

Any duration increase on a critical path activity directly extends the project end date by the same amount.

Question 5

What does Interfering Float (also called Interfering Slack) represent?

Accepted Answer

The difference between Total Float and Free Float

Answer

Interfering Float = Total Float − Free Float, representing float that, if used, would delay a successor's Early Start.

(CST) Certified Scheduling Technician Practice Test

(CST) Certified Scheduling Technician Practice Test

CST Critical Path & Float Analysis 2