What you practice
Each project comes from the same kind of precedence table as the network page. A cascade chart puts every activity on its own row, starting as early as it can, with its total float as a dashed box after it. You read float, latest start and latest finish times off the chart, draw a chart from a table, and add up the workers under way at each time to build a resource histogram. The lower bound is the total work divided by the project length, rounded up.
Questions
How do you draw a Gantt chart from a network?
Work out each activity’s earliest start and duration, then draw one bar per activity starting at its earliest start. A cascade chart puts each activity on its own row. Show the total float as a dashed box after the bar, so you can see how far it could slide.
What does the dashed box on a cascade chart show?
The total float: how far the activity can move to the right without delaying the project. Its right end is the latest finish time, so the latest start is the earliest start plus the float. Critical activities have no dashed box.
How do you work out the lower bound for the number of workers?
Add up the work (each duration times the workers it needs), divide by the minimum project duration and round up. With one worker per activity that is the total of the durations divided by the critical path length. Fewer workers could not finish in time.
What is a resource histogram?
A bar chart of how many workers are needed in each unit of time when every activity starts as early as possible. Add up the workers of every activity under way in that interval. Moving activities within their float can level out the peaks.
Sources, read October 27, 2026: AQA A-level Business 3.10.3; Edexcel A level Business 3.3.4 (PDF); OCR H431 (PDF); Eduqas A level Business (PDF); WJEC CPA activity (PDF); Cambridge 9609 syllabus 2026 to 2028 (PDF), 9.3.5, and its mark schemes; Edexcel Further Maths, Decision 1 topic 4 (PDF).