Question

2. Using the information in Table 1, assuming that the project team will work a standard working week (5 working days in 1 week) and that all tasks will start as soon as possible: Table 1: Project description Task Description Predecessor/s Duration (working days) 5 15 25 15 A B A B с D E F G H Requirement Analysis Systems Design Programming Telecoms Hardware Installation Integration System Testing Training/Support Handover and Go-Live B B 30 CD E, F 10 10 5 5 G H - (i) (ii) (iii) Determine the critical path of the project Calculate the planned duration of the project in weeks Identify any non-critical tasks and the total slack on each

Answer 1

10 15 10 5 CH I B) D 30

ES for first Activity = 0

ES = Maximum (EF of all the predecessors)

EF = ES + Duration

LF for last activity = EF of last activity

LF = Minimum (LS of all the successors)

LS = LF - Duration

Slack = LF - EF = LS - ES

If Slack = 0, Critical.....Else, Not critical

Activity	Duration	ES	EF	LS	LF	Slack	Critical
A	5	0	5	0	5	0	Yes
B	15	5	20	5	20	0	Yes
C	25	20	45	20	45	0	Yes
D	15	20	35	30	45	10	No
E	30	20	50	25	55	5	No
F	10	45	55	45	55	0	Yes
G	10	55	65	55	65	0	Yes
H	5	65	70	65	70	0	Yes
I	5	70	75	70	75	0	Yes

(i)

Critical Path of the project --->

A - B - C - F - G - H - I

(ii)

Planned duration = Time taken by the critical path = 5 + 15 + 25 + 10 + 10 + 5 + 5 = 75 days = 75 / 5 = 15 weeks

(iii) Non critical activities with total slack are listeb below:

Non critical activities Total Slack  

D 10

E 5