Gantt charts and schedulingEdexcel International A Level Maths: Flashcards

Exam questions on Gantt charts and scheduling

1. A project has seven activities. Their durations in days and immediate predecessors are: A (4 days, none); B (3 days, none); C (5 days, A); D (6 days, A); E (4 days, B and C); F (2 days, D); G (3 days, E and F). A cascade (Gantt) chart is to be drawn with every activity starting at its earliest start time.
   Calculate the total float of activity D, and state the latest time at which D can start without delaying the project.2 marks
2. A project has six activities. Their durations in days and immediate predecessors are: P (5 days, none); Q (3 days, none); R (4 days, P); S (5 days, P); T (2 days, Q and R); U (3 days, S and T). Every activity starts at its earliest start time, and the minimum completion time is 14 days.
   Show that at least 2 workers are needed to complete the project in the minimum time.2 marks
3. A workshop job has six tasks. Their durations in hours and immediate predecessors are: A (3 hours, none); B (5 hours, none); C (4 hours, A); D (6 hours, B); E (2 hours, A and B); F (3 hours, C, D and E). Each task is done by one worker without interruption, and a worker can do only one task at a time.
   Find the minimum time in which the job can be completed with as many workers as are needed, and a lower bound for the number of workers needed to complete it in that time.3 marks