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Fundamentals of Project Management



                      Notes         At Event 3, we have to evaluate two predecessor activities – Activity 1-3 and Activity 2-3, both of
                                    which are predecessor activities. Activity 1-3 gives us an Earliest Start of 3 weeks at Event 3.
                                    However, Activity 2-3 also has to be completed before Event 3 can begin. Along this route, the
                                    Earliest Start would be 4 + 0 = 4. The rule is to take the longer (bigger) of the two Earliest Starts.
                                    So the Earliest Start at event 3 is 4.

                                    Similarly, at Event 4, we find we have to evaluate two predecessor activities – Activity 2-4 and
                                    Activity 3-4. Along Activity 2-4, the Earliest Start at Event 4 would be 10 wks, but along Activity
                                    3-4, the Earliest Start at Event 4 would be 11 wks. Since 11 wks is larger than 10 wks, we select it
                                    as the Earliest Start at Event 4. We have now found the longest path through the network. It will
                                    take 11 weeks along activities 1-2, 2-3 and 3-4. This is the Critical Path.




                                        Task  Describe the steps for drawing the CPM/PERT Network.

                                    The Backward Pass – Latest Finish Time Rule

                                    To make the Backward Pass, we begin at the sink or the final event and work backwards to the
                                    first event.























                                    At Event 3 there is only one activity, Activity 3-4 in the backward pass, and we find that the value
                                    is 11–7 = 4 weeks. However at Event 2 we have to evaluate 2 activities, 2-3 and 2-4. We find that
                                    the backward pass through 2-4 gives us a value of 11–6 = 5 while 2-3 gives us 4–0 = 4. We take
                                    the smaller value of 4 on the backward pass.

                                    Self Assessment

                                    State whether the following statements are True or False:
                                    5.   Planning, Scheduling and Control are considered to be advanced Managerial functions.
                                    6.   There are many variations of CPM/PERT which have been useful in planning costs,
                                         scheduling manpower and machine time.
                                    7.   Non-critical activities can be replanned, rescheduled and resources for them can be
                                         reallocated flexibly.
                                    8.   Each activity in a PERT/CPM Network is represented by a circle symbol.





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