Derive the probability distribution of the completion times:

a. The following probability distributions relate to the completion times, in weeks, T_A and T_B of two independent activities, A and B respectively.

The activities A and B form a important phase of a project.

i). Derive the probability distribution of the completion times of this phase if the two activities are undertaken in:

                a. series

                b. parallel

ii) For each of the distribution in (i) above, calculate their relevant statistics.

A task is known to have the following time to completion (in days), T and cost, C probability distribution, respectively:     T » N(20,25)

The distribution of C is conditional on T and is given by:

Calculate:

i). Pr(T£25);

ii Pr(C£2200).