Question

The estimated times and immediate predecessors for the activities in a project at Howard Umrah's retinal scanning company are given in the following table. Assume that the activity times are independent 

This exercise contains only parts a, b, c, d, and e. 

a) Based on the activity time estimates, the expected times and variance for each of the activities are (round your response to two decimal places): 

	Expected
Activity	Time	Warlance
A	9.83	0.26
0	10.33	6.44
C	10.00	1.00
0	10.00	1.78

b) The expected completion time of the critical path weeks fround your response to two decimal places

Answer 1

(a)

				Expected time	Variance
Activity	a	m	b	te = (a + 4m + b)/6	(b - a)2/36
A	8	10	11	9.83	0.25
B	4	10	18	10.33	5.44
C	7	10	13	10.00	1.00
D	6	10	14	10.00	1.78

(b)

Path	Expected duration
A-C	19.83
B-D	20.33

The longest and hence the critical path is B-D and the expected duration is 20.33 weeks.