If the expected time of completion of a project is 60 weeks with a standard deviation of 5 weeks, the probability of completing the project in 50 weeks and 65 weeks respectively will be
A. 2.3% and 84.1%
B. 97.7% and 84.1%
C. 97.7 % and 15.9%
D. 15.9% and 97.7%
Answer: Option A

Z=(Ts-Te)/sigma
Z = (50-60)/5 = -2
Z =(65-60)/5 = 1
By this
Probability is 2.28% corresponding to Z = -2
Probability is 84.13% corresponding to Z= 1
How to solve it