A project has 8 activates The project completion time must b

A project has 8 activates. The project completion time must be shortened by 3 days. Activity A, 29 days, IP: none, $55 per day, 3 days Activity B, 33 days, IP: none, $47 per day; 3 days Activity C, 40 days, IP none: $59 per day; 3 days Activity D, 25 days, IP:A $41 per day; 3 days Activity E, 38 days, IP: B, $54 per day; 3 days Activity F, 29 days, IP: C; $44 per day; 3 days Activity G, 36 days, IP: D; $30 per day; 1 day Activity K, 20 days, IP: E, F, $86 per day; 1 day The above information signifies that activity D has a duration of 25 days, has activity A as its immediate predecessor Furthermore, its crashing cost is $41 per day and it can be crashed for maximum of 3 days The minimum cost to crash the project by 1 day is $ The minimum cost to crash the project by 2 days is $ The minimum cost to crash the project by 3 days is $

Solution

only A,B and C have no immediate predecessors, thus any of three of them can be started first.

G has the minimum of crashing cost and can crash for 1 day. So if we start by either B or C and then go to E , F , K and then A, D, G we will the minimum cost to crash the project by 1 day as $30

D has the second least crashing cost ($41) and also comes at second last in the above sequence. Thus the minimum cost to crash the project by 2 days = 30 + 41 = $71

Since D can be crashed for maximum 3 days, the minimum cost to crash project by 3 days = 30 + 41 + 41 = $112