Problem:
Kozar International, Inc. begun marketing a new instant-developing film project. The estimates of R&D activity time (weeks) for Kozar’s project are given in the table below. The project has two paths: A-C-E-F and A-B-D-F. Assume the activity times are independent.
a) The company wants to be 95% confident that it can deliver the project without incurring any penalty, what time frame should it specify in the bid for project completion time?
b) If the time to complete the path A-B-D-F is normally distributed, what is the probability that this path will take at least 38 weeks to be completed?
|
|
|
Time(weeks)
|
|
|
|
Activity
|
Predecessors
|
Optimistic
time
|
Probable time
|
Pessimistic
time
|
mean
|
Variance
|
|
A
|
-
|
9
|
9
|
9
|
9
|
0.00
|
|
B
|
A
|
8
|
10
|
12
|
10
|
0.44
|
|
C
|
A
|
9
|
12
|
18
|
12.5
|
2.25
|
|
D
|
B
|
5
|
8
|
11
|
8
|
1.00
|
|
E
|
C
|
5
|
7
|
10
|
7.166
|
0.69
|
|
F
|
D, E
|
10
|
12
|
14
|
12
|
0.44
|