How do we schedule dependent tasks to finish a project in the shortest time?
Construct an activity network, compute earliest and latest starting times and float, and identify the critical path and minimum completion time.
How to build an activity network from a precedence table, run forward and backward passes for earliest and latest start times, compute float, and identify the critical path and minimum project duration.
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What this dot point is asking
You must build an activity network from precedence information, run the forward and backward passes, compute float, and identify the critical path and minimum project duration.
The activity network
Tasks with durations and precedence requirements (which task must finish before another can start) are drawn as a directed network. The minimum completion time is the length of the longest path through the network, because every dependent task must wait for its predecessors.
Forward and backward passes
Two sweeps through the network give the timing of every activity.
Float and the critical path
Float (slack) is how long an activity can be delayed without delaying the whole project.
Why float matters
Float tells a project manager which activities have spare time and which must be watched closely. Non-critical activities can absorb delays; critical activities cannot. Speeding up the project means shortening an activity on the critical path, since shortening a non-critical one changes nothing.