The expected activity time in PERT analysis is calculated as:

the sum of the optimistic, persimistic, and most lakly times, divided by six.

the sum of the activity variances, divided by six.

the simple average of the optimistic, pessimistic, and most likeiy times. The form of the optimister pecimaistic, and mast likely times. The weighted aytrage of a m$,$ and b wich wn weighed $4$ times as heavily as a and b$.$