Question

The following tasks lie on the critical path of a project:

Answer 1

Answer:

The correct answer is option (a)  Less than 5% but more than 3%

Explanation:

Scheduled time of project = 25

Calculating the activity variance, we have

Task     Mean time    Standard deviation        Variance

A                  4                               0.6               0.6² = 0.36

B                  5                               0.2               0.2² = 0.04

E                 2                                0.1                 0.1² = 0.01

F                 6                                  1                     1² = 1

H                 2                               0.2                 0.2² = 0.04

M                 6                               0.1                 0.1² = 0.01

Sum of variance = 0.36 +0.04 + 0.01 +1+ 0.04 + 0.01

                                =1.46

Standard deviation  = √variance

                                 =√1.46

                                 =1.2083

probability that the project will be completed in 23 days or less

z = 23-25 /1.2083

     = -1.65

which corresponds to prob. of 0.0494 = 4.94%

a is correct.