What is the formula for calculating float time for non-critical activities?

The formula for calculating float time for non-critical activities is indeed based on the relationship between early start times (EST), late start times (LST), and the duration of the activity. To find the float time, you essentially assess how much flexibility you have in scheduling a non-critical task without delaying the overall project timeline.

The correct formula, which is accurately represented in the chosen answer, considers the late start time of the next activity (LSTnext), the early start time of the current activity (ESTnext), and the time already spent on the activity (activity time used). By subtracting both the early start time and the actual time utilized from the late start time, you can calculate the float time accurately.

This formula allows you to identify how much "extra" time there is for a non-critical activity before its delay impacts subsequent tasks in a project. Non-critical activities are those that have some degree of scheduling flexibility, and understanding their float time is essential for effective project management.

The other options do not provide the correct comprehensive view for calculating float time. They either omit critical aspects like the consideration of activity time used or misinterpret the relationships between those timings. This is why the formula outlined in the correct answer effectively captures the necessary components to