HW-4: Priority rules Processing times (including setup times) and due dates for four jobs waiting to be processed at a work center are given in the following table. Determine the sequence of jobs, the average flow time, average tardiness, and average number of jobs at the work center, for each of these rules: a. FCFS b. SPT C. EDD d. CR Job Processing time(days) 4 3 B D Due date (days) 11 9 7 5 8 7 Solution: FCFS Rule Job Processing time (days) Flow time Due date (days) Tardy days Order SPT Rule Job Processing time (days) Flow time Due date (days) Tardy days Order EDD Rule Job Processing time (days) Flow time Due date (days) Tardy days Order Critical Ratio Rule Job Processing time (days) Due date (days) Critical Ratio Calculations Order Job Processing time (days) Due date (days) Critical Ratio Calculations Order Job Processing time (days) Due date (days) Critical Ratio Calculations Order Critical Ratio Rule Job Processing time (days) Order Flow time Due date (days) Tardy days Comparison of the four rules: Rule Average Processing time (days) average tardiness (days) and average number of jobs/day FCFS SPT EDD CR Which rule is the best