1

enter image description here

From the given table one can draw the project/activity network above. There are four possible paths: (i) C, B. (ii) C, A, D. (iii) E, D. (iv) G, F, D. The first path's project time is 4+5=9, the second path's project time is 4+2+9=15, the third path's project time is 3+9=12, and the forth path's project time is 8+1+9=18. The path the exercise chose is the longest, i.e. the forth path. The exercise didn't specify if the problem was either longest path problem or shortest path problem, and what I want to know is why is project time 18 (longest path) is the correct answer and not 9 (shortest path), is it generally agreed on the longest path or is the exercise missing keywords "longest path problem"?

Also, I would like to know if the following is correct or not; critical activities are the activities that the longest/shortest path takes, e.g. in this case the critical activities are G, F, D.

Dick Armstrong
  • 443

1 Answers1

2

For project management generally, the longest path is the critical path. The reason is that any slip in the duration will cause the project to be delayed. This is not the case for non-critical paths, unless the delay is sufficient to make it become critical.

Dr Xorile
  • 1,407
  • From what I can tell, critical path and critical activities are the same thing, if that is indeed the case, then can they be used interchangeably? Thank you! – Dick Armstrong Aug 23 '15 at 02:55
  • 1
    Critical activities are simply activities that are on the critical path (or paths). – Dr Xorile Aug 23 '15 at 02:58
  • 1
    In your diagram, A through G are activities, while I-III-IV-V (or G, F, D) forms the critical path. – Dr Xorile Aug 23 '15 at 03:00