OPERATIONS RESEARCH 2 COURSE . IT CAN BE PREPARED BY HANDWRTNG OR SOFTWARE.

2. KAB Wiring and Electric is a company that installs wiring and electrical fixtures in residential construction. Ali Koral, CEO of the company, has been concerned with the amount of time that it takes to complete wiring jobs. Some of his workers are very unreliable. A list of activities and their optimistic, pessimistic, and most likely completion times in days are given in the following table: Completion Times (days) Optimistic Most Likely Pessimistic Activity Immediate Predesessors M A 1 2 3 B 5 6 7 A, E 1 1 1 7 E M 2 4 6 H A 6 10 14 M B 4 6 8 a. Determine the probability that the project will be completed within 23 days. b. Compute an interval estimate of the number of days to complete the project for probability of 96.6%. c. Compute the probability that the project will take longer than "expected completion time + 2.5" days