Question

We ask the engineers working on activity A to factor in uncertainty in activity times and to provide better estimates of the activity times. The engineers tell us that activity A takes 2 weeks 25% of the time, 4 weeks 50% of the time and 6 weeks 25% of the time. How long does the project now take to complete (on average)

Answer 1

On average, the project takes 4 weeks to complete.

Explanation:

We have these following probabilities:

25% probability that the activity takes 2 weeks.

50% probability that the activity takes 4 weeks.

25% probability that the activity takes 6 weeks.

How long does the project now take to complete (on average)

We multiply each duration by it's probability.

0.25*2 + 0.5*4 + 0.25*6 = 4

On average, the project takes 4 weeks to complete.