operational management

786 ChapterSeventeen ProjectManagemeni

12. A project manager has compiled a list of major activities that will be required to install a computer

iniormation system in her firm. The list includes estimated completion times for activities and pre-

cedence relationships.

lmmediate

Activity Predecessor Estimated Times (weeks) A

D

E

H

F

G

B

I

J

K

c

M

N

0 End

A

D

E

A F

2-4-6

6-8-10

7 -9-12

2-3-5

3-4-8

5-7-9

2-2-3

2-3-6

3-4-5

4-5-8

5-8- 1 2

1-1-1

6-7-1 1

8-9-1 3

B

I

J

C

M

N

H,G,K,O

a. Construct an activity-on-node diagram for this prqect' b. If the project is finished within 26 weeks of its start, the project manager will receive a bonus of

$1,000; and if the project is finished within 27 weeks of its start, the bonus will be $500' Find

the probability of each bonus.

13. Here is a list of activity times for a project as well as crashing costs for its activities. Determine

which activities should be crashed and the total cost of crashing if the goal is to shorten the project

by three weeks as cheaply as possible.

Activity Duration (weeks) First Grash Second Crash

1-2 5 2-4 6 4-7 3 1-3 3 3-4 7 1-5 5 5-6 5 6-7 5

$8 $10 7s 14 15 I 11 89 10 15 11 13 12 14

14. The project manager of a task force planning the construction of a domed stadium had hoped to be

able io complete construction prior to the start ofthe next college football season. After reviewing

construction time estimates, it now appears that a certain amount of crashing will be needed to ensure project completion before the season opener. Given the following time and cost estimates,

determine a minimum-cost crashing schedule that will shave five weeks off the project length. Nole.' No activity can be crashed more than two weeks.

7-10-12