Project Management
Forecasting
Please provide detailed solutions to
the following problems/exercises (4 problems/exercises):
1)
Draw the network corresponding to the following information. Complete the
table, identify the critical path, and specify project completion time.
Activity 
Immediate 
Time (Weeks) 
A 
— 
3 
B 
— 
4 
C 
A 
6 
D 
B 
9 
E 
B 
6 
F 
C,D 
6 
G 
D,E 
8 
H 
G,F 
9 
Activity 
Earliest Start 
Earliest Finish 
Latest Start 
Latest Finish 
Slack 
A 

B 

C 

D 

E 

F 

G 

H 
2)
Consider the tasks, durations, and predecessor relationships in the following
network. Draw the network and answer the questions that follow.
Activity 
Immediate Predecessor(s) 
Optimistic (Weeks) 
Most Likely (Weeks) 
Pessimistic (Weeks) 
A 
— 
4 
7 
10 
B 
A 
2 
8 
20 
C 
A 
8 
12 
16 
D 
B 
1 
2 
3 
E 
D, C 
6 
8 
22 
F 
C 
2 
3 
4 
G 
F 
2 
2 
2 
H 
F 
6 
8 
10 
I 
E, G, H 
4 
8 
12 
J 
I 
1 
2 
3 
a. What is the expected time for activity B?
b. What is the variance for activity B?
c. Based on the calculation of estimated times, what is the critical
path?
d. What is the estimated time of the critical path?
e. What is the activity variance along the critical path?
f. What is the probability of completion of the project before week
42?
3)
Develop forecasts for periods 7 through 10 for the demand data in the table
using a three period moving average, a weighted moving average using 0.6, 0.3,
and 0.1, and exponential smoothing with alpha = 0.7. Use a 6th period forecast
of 135 as the starting point for the exponential smoothing technique.
Period 
Actual 
MA n=3 
WMA 
Exp. Smoothing 
1 
64 

2 
84 

3 
91 

4 
97 

5 
115 

6 
135 

7 
137 

8 
144 

9 
153 

10 
171 
4)
Using the data shown in the table, develop a trend line that can be used to
predict the demand for time period number 20. What is the prediction equation
and what is your forecast for period 20?
Period 
Demand 
Demand2 
Period*Demand 

1 
16 

2 
20 

3 
24 

4 
27 

5 
29 

6 
30 

7 
32 

8 
35 

9 
36 

10 
38 

Sums 
55 
287 