8. A company is planning a small project and the following table gives the various activities in that project, as well as their associated completion times. Activity A B D E F G Completion time (days) 5 6 7 4 2 1 5 Here, for example, activity D takes 4 days to be completed. The immediate precedence relationships are: Activity A B D E G must be finished before must be finished before must be finished before must be finished before must be finished before Activity B CE E F D.B can start can start can start can start can start In addition: 4 days must elapse between the end of activity D and the start of activity C 2 days must elapse between the end of activity F and the start of activity C (a) Draw the network diagram and calculate the overall project completion time. State the critical path(s). (12 marks) (b) Copy the following table into your answer and fill in the latest start times. Latest start time (days) Activity A B D E F G (4 marks) (c) A colleague who has considered the same network as that given above believes that the project completion time is 27 They have also produced the following table of latest start times. Activity B D E F G Latest start time (days) 0 5 20 11 15 17 0 Your immediate superior believes that your colleague has made a mistake in their consideration of the network, namely either that they have used a wrong value for one of the activity completion times, or that they have not included one of the precedence relationships. Clearly explaining your reasoning what mistake (if any) has your colleague made? (9 marks) 8. A company is planning a small project and the following table gives the various activities in that project, as well as their associated completion times. Activity A B D E F G Completion time (days) 5 6 7 4 2 1 5 Here, for example, activity D takes 4 days to be completed. The immediate precedence relationships are: Activity A B D E G must be finished before must be finished before must be finished before must be finished before must be finished before Activity B CE E F D.B can start can start can start can start can start In addition: 4 days must elapse between the end of activity D and the start of activity C 2 days must elapse between the end of activity F and the start of activity C (a) Draw the network diagram and calculate the overall project completion time. State the critical path(s). (12 marks) (b) Copy the following table into your answer and fill in the latest start times. Latest start time (days) Activity A B D E F G (4 marks) (c) A colleague who has considered the same network as that given above believes that the project completion time is 27 They have also produced the following table of latest start times. Activity B D E F G Latest start time (days) 0 5 20 11 15 17 0 Your immediate superior believes that your colleague has made a mistake in their consideration of the network, namely either that they have used a wrong value for one of the activity completion times, or that they have not included one of the precedence relationships. Clearly explaining your reasoning what mistake (if any) has your colleague made? (9 marks)
