probability

probability
The project manager of Good Public Relations gathered the data shown in Table for a new advertising campaign.
a. How long is the project likely to take?
b. What is the probability that the project will take more than 38 weeks?
c. Consider the path A-E-G-H-J. What is the probability that this path will exceed the expected project duration?
ACTIVITY DATA FOR ADVERTISING PROJECT
Time Estimates (weeks)
A
8
10
12
START
B
5
8
17
START
C
7
8
9
START
D
1
2
3
B
E
8
10
12
A,C
F
5
6
7
D, E
G
1
3
5
D,E
H
2
5
8
F,G
I
2
4
6
G
J
4
5
8
H
K
2
2
2
H