Activity	$T_{o}$	$T_{m}$	$T_{p}$
10-20	3	6	9
10-30	4	6	8
20-40	5	7	9
20-50	10	12	16
30-50	5	6	7
40-70	8	10	12
40-60	9	10	11
50-60	2	4	8
60-70	3	6	12

Z	-3	-2	-1	0	1	2	3
P%	0.13	2.28	15.87	50	84.13	97.72	99.87

i) Calculate project duration for 50 % probability.

ii) Workout probability of competition in 22 days.

Project duration = 29.5 days

Critical path = 10-20-40-70 = 10-20-60-70

Step 3:

Probability (%) = 50 %

For 50 % probability, the scheduled time will be same as that of the project duration i.e. 29.5 days.

ii) For project duration = 22 days

S.T.= 22 days

P.D.= 29.5 days …