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These are the user uploaded subtitles that are being translated: 1 1 00:00:01,310 --> 00:00:03,460 Here's the forward pass. 2 2 00:00:03,460 --> 00:00:06,480 We start at the beginning and scan forward 3 3 00:00:06,480 --> 00:00:09,853 to find the earliest everything can start and finish. 4 4 00:00:11,760 --> 00:00:15,950 Remember, for the forward pass, if a deliverable has more 5 5 00:00:15,950 --> 00:00:20,580 than one predecessor, we copy the greatest, earliest finish 6 6 00:00:20,580 --> 00:00:23,763 of all the predecessors to the deliverable's earliest start. 7 7 00:00:25,250 --> 00:00:27,490 Then we add the earliest start and the duration 8 8 00:00:27,490 --> 00:00:30,320 to get the deliverable's earliest finish. 9 9 00:00:30,320 --> 00:00:31,730 And we write these numbers on the top 10 10 00:00:31,730 --> 00:00:33,780 of the deliverable to keep track of them. 11 11 00:00:35,860 --> 00:00:38,780 We start at day zero because of the way addition works. 12 12 00:00:38,780 --> 00:00:41,490 So the earliest day the kickoff meeting can start 13 13 00:00:41,490 --> 00:00:43,163 is immediately after day zero. 14 14 00:00:44,100 --> 00:00:47,050 Since we are going forward, we add numbers, and the duration 15 15 00:00:47,050 --> 00:00:48,800 of the kickoff meeting is one day, 16 16 00:00:48,800 --> 00:00:50,190 so the earliest day it can finish 17 17 00:00:50,190 --> 00:00:51,863 is zero plus one or day one. 18 18 00:00:52,890 --> 00:00:54,950 We write the earliest start at the top left 19 19 00:00:54,950 --> 00:00:57,550 and the earliest finish at the top right of the deliverable. 20 20 00:00:59,150 --> 00:01:01,910 Now let's look at the new floor plan first draft. 21 21 00:01:01,910 --> 00:01:04,970 It only has one predecessor, so we simply copy 22 22 00:01:04,970 --> 00:01:08,670 over the earliest finish of the kickoff meeting day one 23 23 00:01:08,670 --> 00:01:10,410 as the earliest day after which 24 24 00:01:10,410 --> 00:01:12,460 the new floor plan first draft can start. 25 25 00:01:13,630 --> 00:01:16,110 The new floor plan first draft is four days in duration 26 26 00:01:16,110 --> 00:01:19,710 so the earliest it can finish is one plus four or day five, 27 27 00:01:19,710 --> 00:01:22,460 and we record that on the top right of the deliverable. 28 28 00:01:23,810 --> 00:01:26,500 Now we can't go forward to the executive review yet 29 29 00:01:26,500 --> 00:01:28,690 because it has two predecessors, 30 30 00:01:28,690 --> 00:01:31,690 including the new department processes first draft. 31 31 00:01:31,690 --> 00:01:33,290 So we need to know the earliest 32 32 00:01:33,290 --> 00:01:35,963 the new department processes first draft can finish. 33 33 00:01:37,070 --> 00:01:39,310 Once again, we copy over the earliest finish 34 34 00:01:39,310 --> 00:01:42,510 of the kickoff meeting day one as the earliest start 35 35 00:01:42,510 --> 00:01:45,330 for the new department processes first draft. 36 36 00:01:45,330 --> 00:01:47,380 The new department processes first draft are ten days 37 37 00:01:47,380 --> 00:01:49,760 in duration so the earliest they can finish 38 38 00:01:49,760 --> 00:01:52,340 is one plus 10 or day 11, 39 39 00:01:52,340 --> 00:01:54,090 and we write that on the top right. 40 40 00:01:55,290 --> 00:01:57,690 Now we can move forward to the executive review. 41 41 00:01:58,610 --> 00:02:01,003 If you get this step, you get it all. 42 42 00:02:01,890 --> 00:02:04,240 According to the logic of the project, 43 43 00:02:04,240 --> 00:02:07,350 we can't start the executive review until both 44 44 00:02:07,350 --> 00:02:09,240 of the predecessors are finished: 45 45 00:02:09,240 --> 00:02:10,780 the new floor plan first draft 46 46 00:02:10,780 --> 00:02:13,053 and the new department processes first draft. 47 47 00:02:13,950 --> 00:02:16,430 One might be finished; good for them. 48 48 00:02:16,430 --> 00:02:17,940 But they both have to be finished 49 49 00:02:17,940 --> 00:02:19,440 to start the executive review. 50 50 00:02:20,330 --> 00:02:21,620 So what's the earliest day 51 51 00:02:21,620 --> 00:02:24,380 after which the executive review can start? 52 52 00:02:24,380 --> 00:02:28,030 It's the greatest of the predecessors' earliest finishes, 53 53 00:02:28,030 --> 00:02:29,420 which is day 11 54 54 00:02:29,420 --> 00:02:31,793 for the new department processes first draft. 55 55 00:02:32,940 --> 00:02:36,440 At this point, the new department processes first draft 56 56 00:02:36,440 --> 00:02:38,560 are what's driving the schedule 57 57 00:02:38,560 --> 00:02:41,943 and determining the earliest the executive review can start. 58 58 00:02:43,100 --> 00:02:46,733 This is the key concept of the critical path process. 59 59 00:02:48,890 --> 00:02:52,050 So we simply carry this process on, at each step 60 60 00:02:52,050 --> 00:02:55,610 copying the predecessor's greatest, earliest finish 61 61 00:02:55,610 --> 00:02:58,170 to the next deliverable's earliest start, 62 62 00:02:58,170 --> 00:03:01,640 determining the longest path through the project, 63 63 00:03:01,640 --> 00:03:03,883 and so how long the whole project will take. 64 64 00:03:05,730 --> 00:03:09,080 For example, you can see the executive approval 65 65 00:03:09,080 --> 00:03:13,170 can start no earlier than one day after day 22 66 66 00:03:13,170 --> 00:03:15,950 because it has to wait for its longest predecessor, 67 67 00:03:15,950 --> 00:03:17,450 the finish of the one-page FAQ. 68 68 00:03:18,960 --> 00:03:23,600 Similarly, along the bottom, the training manual first draft 69 69 00:03:23,600 --> 00:03:25,010 can start no earlier than one day 70 70 00:03:25,010 --> 00:03:27,350 after day 12 because it has to wait 71 71 00:03:27,350 --> 00:03:29,300 for the finish of the executive review. 72 72 00:03:31,200 --> 00:03:34,040 And the training manual second draft can start no earlier 73 73 00:03:34,040 --> 00:03:37,630 than one day after day 23 because it needs completion 74 74 00:03:37,630 --> 00:03:38,943 of the executive approval. 75 75 00:03:40,560 --> 00:03:43,640 By carrying forward this process to the end of the project, 76 76 00:03:43,640 --> 00:03:45,890 we calculate that the longest path 77 77 00:03:45,890 --> 00:03:48,373 through the project is 34 days. 78 78 00:03:49,420 --> 00:03:51,660 The project can't be done any faster than that 79 79 00:03:51,660 --> 00:03:55,520 since there are 34 days of back-to-back work 80 80 00:03:55,520 --> 00:03:56,570 on the critical path. 81 81 00:03:58,660 --> 00:04:02,170 Now, you could probably see the critical path 82 82 00:04:02,170 --> 00:04:04,503 that is driving this 34-day schedule. 83 83 00:04:05,660 --> 00:04:08,410 But let's do the backwards path so we understand 84 84 00:04:08,410 --> 00:04:11,700 in our bones how the critical path is determined 85 85 00:04:11,700 --> 00:04:15,763 and can calculate the float of the rest of the deliverables. 7697