Question

In CPM method of network analysis the Critical activities are associated with

• A. Maximum Float
• B. Minimum Float
• C. Negative Float
• D. Zero Float

Hint:

The name says it all: the activity is "critical" precisely because it has no "float" or leeway.
It must start and end on time to avoid delaying the project.
Critical Path = Longest Path = Path of Zero Float.

Answer 1

The Correct Option is D

Step 1: Recall what float actually measures.
Float, or slack, tells us how much an activity's completion can slip without pushing back the finish date of the whole project.
Step 2: Think about what makes the critical path critical.
The critical path is the longest chain of dependent activities in the network, and since the project cannot finish before this longest chain finishes, every activity sitting on this path is already running at the tightest possible schedule with no room to spare.
Step 3: Connect this tightness to the float value.
If any activity on this longest chain were delayed even slightly, that delay would directly push out the entire project completion date, which means these activities have absolutely no spare time, in float terms that spare time is exactly zero.
Step 4: Conclude.
So critical activities, by their very definition of having no slack, always carry zero float.
\[ \boxed{\text{Zero Float}} \]