Question

In the CPM time-cost trade-off function

Select one:

a. the cost at normal time is zero.

b. in the range of feasible times, the activity cost increases linearly as time increases.

c. cost deceases linearly as time increases.

d. none of the above.

e. All of the above.

Answer 1

Cost at normal time cannot be zero. It is some positive cost called the normal cost.

Cost cannot increase as time increases. In fact, as we need less duration, we need to invest more in the activity cost.

The activity cost will not decrease if we settle for more than the normal time because the normal cost is the minimum possible activity cost.

So, none of (a), (b), (c) are actually correct.

The activity cost or the direct cost will increase for reducing the time of an activity from its normal time. But at the same time, the indirect cost will decrease by reducing the time of the activity from its normal time. This is the trade-off.