Scheduling a project by CPM: What are the essential steps? When preparing a CPM schedule for an engineering project, which set of actions correctly describes the overall process?
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ADivide project into activities and sequence only
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BEstimate times only and draw bar chart
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CDraw the network only and compute floats later
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DAll the above (activities defined, durations estimated, logical sequence set, and the network drawn)
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E
Answer
Correct Answer: All the above (activities defined, durations estimated, logical sequence set, and the network drawn)
Explanation
Introduction / Context:CPM (Critical Path Method) is a deterministic scheduling technique used to plan, monitor, and control project timelines. It relies on a clear breakdown of work, time estimates, precedence logic, and a network representation from which critical paths and floats are computed.
Given Data / Assumptions:
- The project is suited to CPM (deterministic activity durations).
- All activities can be identified and sequenced logically.
- Accurate time estimates are available or can be developed.
Concept / Approach:The CPM workflow includes: breaking the project into discrete activities; establishing logical relationships among them; estimating durations; and drawing the network (AOA or AON). This allows a forward and backward pass to compute earliest and latest times, floats, and identify the critical path.
Step-by-Step Solution:Identify activities and milestones.Sequence activities using precedence logic.Estimate durations based on productivity data and resource plans.Draw the network and run time analysis to find the critical path and floats.
Verification / Alternative check:Any CPM tutorial or worked example follows these steps, confirming that all listed points collectively form the correct process rather than any single step alone.
Why Other Options Are Wrong:Options a–c each capture only a fragment. CPM requires all steps to work together.
Common Pitfalls:
- Skipping proper activity definition, leading to overlaps or gaps.
- Ignoring precedence constraints while estimating durations, causing unrealistic schedules.
Final Answer:All the above (activities defined, durations estimated, logical sequence set, and the network drawn)