The Three time estimate for different activities of a project are given below:-

Activity	$T_0$	$T_m$	$T_p$
1-2	2	5	8
2-3	4	9	20
2-4	4	7	16
2-5	8	11	20
3-6	3	7	17
4-6	7	10	13
4-5	0	0	0
5-7	3	5	13
6-7	2	3	10
7-8	2	4	6

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

What is the probability of completing the project in 35 Days?

Step 1 :-

For critical activity only

$\sigma = \frac{t_p - t_o}{6}$

Activity	$T_0$	$T_m$	$T_p$	$t_e = \frac{t_0 + 4t_m + t_p}{6}$	$\sigma$	$\sigma^2$
1-2	2	5	8	5	1	1
2-3	4	9	20	6
2-4	4	7	16	8	2	4
2-5	8	11	20	12
3-6 …