Question

Given the following activities and precedents, draw a PERT/CPM diagram.

ACTIVITY	IMMEDIATE PREDECESSOR	DURATION (DAYS)
A	-	10
B	-	12
C	A	4
D	A, B	8
E	A, B	9
F	C	10
G	D, F	12
H	E, G	15

Answer the following:

• What is the critical path?
• How long will it take to complete this project?
• Can activity E be delayed without delaying the completion of the project? If so, how many days?

Answer 1

Activity	ES	EF	LS	LF	Slack
A	0	10	0	10	0
B	0	12	4	16	4
C	10	14	10	14	0
D	12	20	16	24	4
E	12	21	27	36	15
F	14	24	14	24	0
G	24	36	24	36	0
H	36	51	36	51	0

Slack = LS-LF=EF-ES

Critical path is the longest path which is A-C-F-G-H with duration of 51 days

It will take 51 days to complete the project

Activity E has slack of 9 days so E can be delayed by maximum 9 days without delaying the completion of the project