The longest path through the network diagram shown above will be the critical path. The solution appears on the next page.
Critical Path Solution
Notice that:
a. Activities D and E are in a mandatory dependency relationship: activity D must complete before activity E begins. b. Since the combined time for activities D and E is 7weeks, activity G is not on the critical path because it only has a duration of 6 weeks c. Notice that three paths converge into activity I. We determine the critical path by computing the duration of all possible paths to activity I: a. A – B – C-I: 16 weeks b. A – B – F- I: 15 weeks c. A – D – E– F-I : 18 weeks d. A – G – H-I: 18 weeks e. A – D – E – H-I : 19 weeks Also notice that there are 2 ‘near critical’ paths, each at 18 weeks: A-D-E-F-I and A-G-H-I. As the project manager, you would keep an eye on these near critical paths to monitor for any schedule variances. Either one of these paths could become a parallel critical path or a new critical path if activities along these paths were delayed. The diagram that appears below is called an AOA (Activity on Arrow) or ADM (Arrow Diagramming Method). While this approach is not referenced in the PMBOK® Guide, 5th edition, questions addressing AOA diagrams still appear on the exam, so we will cover the basics here.
©℗ 2009-2013 Richard Perrin – Evolutionten: Project Time Management
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