Page 267 - DMGT521_PROJECT_MANAGEMENT

Project Management

Notes of completion if project is delayed by certain period of time. Please note that probability
of being completed by critical time is 50%. If more days are added the probability would
increased and can be quantified by using normal curve method. For this we need a z-table
and astandard deviation. PERT has special formula for calculating Standard Deviation.
First, it would identify the activities on the critical path. Second, it would calculate variance
for each activity on the path. Finally, square-root would be worked of sum total of variances
of activities on the critical path. Necessary working is shown in the right hand side table.
Normal Curve with properties

Probability of completion

Normal Distribution

Normal distribution is natural distribution. I teach Project Management to a class of 40
students. Since all the students are reading from the same books, are being taught by the
same teacher in the same environments, their marks in any test would be normally
distributed. About 68% of the students would gain around the average, a few would well
above it and a few well below. In a recently conducted test, the average score was 80 with
a standard deviation of 6. It means that 68% of them got marks between 74 & 86. There
were few exceptions. A few students were well above 86 while a few were much below 74.
Question:
1. Critically analyse and find out the probability of a student getting marks above
80%.
Source: http://hafeezrm.hubpages.com/hub/CASE-STUDY---Probability-in-PERT

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