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What is the probability that this project will be completed within 130 days?

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The probability that this project will be completed within 130 days is 0.8413.

Expected duration (ED) = (Optimistic + 4 x Most Likely + Pessimistic) ÷ 6.

Affirmative Action

41 Optimistic

Probability = 50

Negative = 59ED = (41 + 4 50 + 59) 6 = 50

50-minute duration

B. Activity

Positive = 54

60 is the most likely number.

Negative = 66ED = (54 + 4 60 + 66) 6 = 60

60-minute duration

C. Activity

Positive = 58

70 is the most likely number.

Negative = 82ED = (58 + 4 70 + 82) 6 = 70

70-minute duration

D's Activity

32 Optimistic

41 is the most likely number.

Negative = 44ED = (32 + 4 41 + 44) 6 = 41

41 minutes.

Project total duration = 50 + 60 + 70 + 41 = 221

Project completion time estimate = 221 days

The critical path's standard deviation is calculated using the following formula:

σ = P - O/6

Where indicates the critical path's standard deviation, P represents the pessimistic time, and O represents the optimistic time.

σ = 66 - 54/6 = 2.

Then there's the chance that this project will be finished in 130 days:

P(z -45.5) = 0 (due to negative value) z = (130 - 221) / 2 = -45.5

P(z -4.5) = 0 (as calculated from the normal distribution table)

As a result, the likelihood that this project will be completed within 130 days is 0.8413.

Complete question:

Consider the following work breakdown structure: Activity A B С D Start Node 1 1 2 3 Finish Node 2 3 Optimistic 41 54 58 32 Duration (days) Most Likely 50 60 70 41 Pessimistic 59 66 82 44 4 4 What is the probability that this project will be completed within 130 days? Multiple Choice O .9544 .8413 O 9987 .9772 190

User Aleksandr Dubinsky
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