Kelle Carpet and Trim installs carpet in commercial offices

Kelle Carpet and Trim installs carpet in commercial offices. Peter Kelile has been very concerned with the amount of time it took to complete several recent jobs. Some of his workers are very unreliable. A list of activities and their optimistic completion time, the most likely completion time, and the pessimistic completion time (all in days) for a new contract are given in the following table Time (days) Immediate Activitya b Predecessor(s) B, D A, E A, E 9 14 10 13 12 17 15 H, I This exercise contains only part a. a) Based on the activity time estimates, the expected times and variance for each of the activities are Round your responses to two decimal places.) Activity Expected Time Variance

Solution

Following are to be noted:

Expected time for any activity = ( a + 4.m + b)/6

Variance for an activity = ( b – a )^2/36

Accordingly, please find below the table highlighting expected time and variance of activities A to K :

Activity

Pessimistic ( a )

Most likely(m)

Optimistic(b)

Expected duration

Variance

A

3

7

8

6.50

0.69

B

3

4

5

4.00

0.11

C

1

2

3

2.00

0.11

D

7

8

9

8.00

0.11

E

1

3

5

3.00

0.44

F

7

9

14

9.50

1.36

G

1

2

3

2.00

0.11

H

5

7

9

7.00

0.44

I

10

11

12

11.00

0.11

J

13

15

17

15.00

0.44

K

4

8

12

8.00

1.78

Activity	Pessimistic ( a )	Most likely(m)	Optimistic(b)	Expected duration	Variance
A	3	7	8	6.50	0.69
B	3	4	5	4.00	0.11
C	1	2	3	2.00	0.11
D	7	8	9	8.00	0.11
E	1	3	5	3.00	0.44
F	7	9	14	9.50	1.36
G	1	2	3	2.00	0.11
H	5	7	9	7.00	0.44
I	10	11	12	11.00	0.11
J	13	15	17	15.00	0.44
K	4	8	12	8.00	1.78