The following table lists the activities needed to complete aproject. The first column lists the activities and the “followsâ€column shows which other activity or activities, (if any), must becompleted before these activities can start. The remaining columnsgive three estimates of the activity duration; the mean durationcalculated from these estimates and standard deviation assuming abeta distribution of activity duration.
Activity | Follows | Estimates of durations (days) |
Optimistic | Most likely | Pessimistic |
|
A | -- | 3 | 6 | 15 |
B | A | 8 | 14 | 26 |
C | A | 1 | 2 | 9 |
D | B | 2 | 5 | 14 |
E | C | 5 | 7 | 21 |
F | D | 2 | 4 | 12 |
G | B, E | 6 | 9 | 18 |
H | F | 1 | 3 | 5 |
I | D, G | 2 | 3 | 10 |
J | G | 5 | 7 | 15 |
a) Calculate mean duration and standard deviation for allactivities using the beta distribution. (4 points)
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b) Construct a network diagram for this problem using the meandurations calculated in part (a), calculate the ES (Prec.),LS(Foll.) and the total float for all the activities, and henceidentify the critical path . What is the mean completion time forthe project? What is the standard deviation of the critical path?(3 0 points)
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c) What is the 99% confidence interval for the length of thecritical path? (4 points)
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d) Assuming that the probability distribution of the length of thecritical path can be approximated by a normal distribution with themean and standard deviation calculated in part (b), calculate theprobability of completing the project within 34 days . (4points)
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e) What is the probability that the project will be completedbetween 38 and 45 days? Show your workings! (4 points)
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f) Answer the project manager’s question:
“I want to tell the client a project length which I am 89.97% surethat we can meet - What figure should I give them?\" (4points)