TIME MANAGEMENT 5
Task1 can start immediately and has an estimated duration of 3weeks.Task 2 can start after Task 1 is completed and has anestimated duration of 3 weeks.Task 3 can start after Task 1 iscompleted and has an estimated duration of 6 weeks.Task 4 canstart after Task 2 is completed and has an estimated duration of 8weeks.Task 5 can start after Task 4 is completed and after Task3 is completed. Task 5 has an estimated duration of 4 weeks.
LetT1 represent task 1
LetT2 represent task 2
LetT3 represent task 3
LetT4 represent task 4
LetT5 represent task 5
Fromthe network diagram, the critical path can be established throughdetermining the available paths in the network diagram and thenfinding the path that has the longest duration (Lockyer& Gordon, 1994). There are only two paths that can be deducedfrom the network diagram.
NB/Since task 5 can only occur after the completion of task 3 and task4, inclusion of a dummy is critical the dummy activity will not haveany effect because it has no time allocation (Lockyer& Gordon, 1994).
Firstpath = T1, T2, T4, T5
Secondpath = T1, T3, T5
Throughcalculating the time taken through these two paths, the time for thefirst path is 3 + 3 + 8 + 5 = 19 weeks. Then, the time for the secondpath is 3 + 6 + 5 = 14 weeks. The first path is the longest durationpath since it requires 19 weeks to finish the tasks up to the task 5.Therefore, the critical path is Task 1, Task 2, Task 4, Task 5. Theduration of the critical path is 19 weeks.
Theslack can be calculated by Latest Time less the Earliest Time. Theslack for Task 3 will be calculated by Latest Time for Task 3 lessEarliest Time for Task 3
LatestTime for Task 3 = 12 weeks
EarliestTime for Task 3 = 9 weeks
Slackfor Task 3 = (12 – 9) weeks
Slackfor Task 2 = Latest Time for Task 2 less Earliest Time for Task 2
LatestTime for Task 2 = 6 weeks
EarliestTime for Task 2 = 6 weeks
Slackfor Task 2 = (6 – 6) weeks
Theslack for Task 2 is equal to zero while that for Task 3 is not equalto zero. This is because Task 2 is among the tasks in the criticalpath. However, since Task 3 is not in the critical path, it impliesthat its slack cannot be zero.
Lockyer,K., & Gordon, J. (1994). Criticalpath analysis and other project network techniques.London: Pitman.