Question

Activity	Duration (days)	Preceding activity
A	3	-
B	5	-
C	2	B
D	1	A
E	6	A
F	3	D
G	3	C,E

a. Construct a network diagram showing the critical path.

b. Identify the earliest time the campaign can start.

c. Identify the activities where there is float/slack time in the project, and calculate how much float/slack time there is.

** You should show all of your workings and state, clearly, any assumptions made.                                              

Answer 1

(a) Network Diagram -

(b)

Earliest Start (ES) = the earliest time when the activity can begin

Earliest Finish (EF) = ES + Activity Duration

Latest Finish (LF) = the latest time by whenthe activity can be finished without changing the project completion duration

Latest Start (LS) = LF - Activity Duration

Slack = LS-ES = LF-EF

Computing using the above gives us the below -

Activity	Precedes	Duration	ES	EF	LS	LF	Slack
A	-	3	0	3	0	3	0
B	-	5	0	5	2	7	2
C	B	2	5	7	7	9	2
D	A	1	3	4	8	9	5
E	A	6	3	9	3	9	0
F	D	3	4	7	9	12	5
G	C, E	3	9	12	9	12	0

Hence, the Earliest time the project can start = 0 days

Slack for A, E, G = 0

Slack for B = 2 days, C = 2 days, D = 5 days, F = 5 days