Question

(iii) Determine the minimum possible project time and the total addirional cost to complete the project in this time. (15 Marks) 2 2 5 5 6 6 4 زرا 4 در Normal Duration Crash Duration Activity Days Cost $ Days Cost $ 1-2 2 450 1 600 1-3 4 400 2 600 1-4 6 350 5 700 2-4 2 250 1 400 3-5 3 100 2 150 4-5 4 500 2 1000 4-6 5 500 3 800 5-6 3 400 2 600

Answer 1

Crash duration for 4 5 2 days Crash duration duration for 5 5 6 a days Total duration of 1 ₃ 4 5 6 After crashing is 5+2+2 9 days Now the path becomes 2 5 (9 5 2 3 4 3 Now the time duration along 66 - 6 is 5+5 10 days This path 066 becomes critical path and duration of project is now 10 days

Now the path along 4 6 has to be Crashed to reduce the o time duration duration of 4 - 6 After crashing = 3 days Now time duration along o is 8 days ( 5+3 But time duratione along o. (4 is 'q'-days and this could not be reduce further *Hence minimum possible project daration of aton project is 9 days -

Additional Cost Required crash cost - Normal Cost Additional cost for 7 4 = 700-350 350 $ Additional Cost for 4 - 5 11 1ooo - 500 500$ Additional Cost for 5 6 = 6oo - 400 200 $ 800-500 Additional Cost for 4₃ 67 for a-days 43 300$ But we have to Total additional costs required 350 $ +500 $ + 2005 + 300$ Total additional Costs required 1350 $