Question

NI!! Al: Determine the expected durations and variance for activities E and F based on the information in the above table. A Assume that delivery date of 68 was promised for this project. Based on values computed in Al, the values in the table, and the network above, determine the probability of being late Note: A normal probability distribution table appears on the last page

Answer 1

Te = (a+4m+b)/6 EF = ES + Te LS = LF - Te Slack = LF - EF Activity Predecessors Std Deviation =(b-a3/6 Variation = std deviation 2 m b Calculation Value Calculation Value Calculation Value Calculation Value NA 0 30 30 0 0 30 43 30 133 43 53 50 3 30 13 20 16 6 5 0+30 30+13 30+20 43+16 50+6 59+5 30-30 43-13 53-20 59-16 59-6 64-5 43 59 25 625 981 4 16 1 1 2 4 1 1 42 728 Std Dev Variance 30-30 43-43 53-50 59-59 59-56 64-64 2 30 43 50 59 L 5 L L 14 8 53 59 64 DE 2 5 (2+4+5+14)/6 (2+4+5+8)/6 Total L 164 59 Project completion time (m): 64 days Critical Path = A-B-D-F A1: Expected duration and variance Activity Duration Variance 1 A2 Let x be the expected project completion time = 68 days s = standard deviation = 42 Actual completion time (m) = 64 days As we know, z= (x-m)/s Putting values in the formula z = (68 - 64)/ 42 = 4/ 42 = 0.10 z score = 0.10 Probability for 2-score (0.10) = 46.02% So, probability that the project will finish in 68 days or less = 46.02%