A list of task durations is not enough to determine a project's finish. Some tasks must wait for others, while some can overlap. Make the dependencies explicit before adding every number into one timeline.
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Write the fictional network
In an original classroom model, task A takes two days. After A finishes, tasks B and C can begin in parallel; B takes three days and C takes five. Task D takes one day and can start only when both B and C are finished.
Assume sufficient separate resources for the parallel work, no waiting delays and continuous calendar-day durations. These assumptions define the model rather than describing an actual team's schedule.
Find the earliest shared finish
A finishes at day two. B can finish at day five, while C finishes at day seven. D must wait until day seven and therefore finishes at day eight.
The total duration is 2 + max(3,5) + 1 = 8 days. Adding 2 + 3 + 5 + 1 = 11 would treat B and C as sequential even though the model allows them to overlap.
Check which branch controls completion
The A-B-D path totals six days; A-C-D totals eight. In this model the longer path determines the earliest completion.
Shortening B from three days to one does not shorten the eight-day finish because C still controls the wait for D. If C is shortened from five days to two, B becomes the longer parallel branch and the total becomes six days, not five.
Revisit resources before using the result
If B and C need the same person or equipment and cannot overlap, the parallel assumption fails. Weekends, handoffs, uncertain durations or additional dependencies can also change the timeline.
This is general project-planning practice relevant to CBPA interests, not an organiser's required plan or a finished student submission. Students should independently map their own permitted work and justify assumptions. A useful review checks start conditions, branch lengths and resource availability before presenting a completion date.
Continue reading: CBPA Team Planning: A Task List Is Not Yet a Timeline.
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Official information and further reading: Source 1
