Question $2(20$ marks$)$

A leading information technology company has a project involving the installation of a

computer system involving eight activities. The following table lists immediate

predecessors, activity times in weeks as well as other relevant information about the

activities.

Activity Immediate

predecessor

activity

Normal

duration

$($weeks$)$

Normal

cost

Crash

time

$($weeks$)$

Cost if

crashed

A $-3$ N$$9001$ N$$1700$

B $-6$ N$$20003$ N$$4000$

C A $2$ N$$5001$ N$$1000$

D B$,$ C $5$ N$$18003$ N$$2400$

E D $4$ N$$15003$ N$$1850$

F E $3$ N$$30001$ N$$3900$

G B$,$ C $9$ N$$80004$ N$$9800$

H F$,$ G $3$ N$$10002$ N$$2000$

FACULTY OF COMMERCE, MANAGEMENT AND LAW

OLD CURRICULUM MODULES

Page $17$ of $18$

Required

Marks

Sub$-$

total Total

$2\mathrm{.}1$

Draw a network diagram based on the normal times given,

illustrating the critical path routes and determine the normal cost and

duration to complete the project.

$66$

$2\mathrm{.}2$ Determine the earliest starting time and the latest starting time of

each activity. $814$

$2\mathrm{.}3$

Assuming that the project has to be completed in $16$ weeks, what

crashing decisions do you recommend to meet the desired

completion time at the least possible cost? Work through the

network and attempt to make the crashing decisions by inspection.

$620$