Strawberry 2 days 6 Peanut 2 days 12 a)SPT rule minimizes the mean flow time. The optimal sequence IS Strawberry-Peanut-Vanilla-Chocolate or Peanut-Strawberry-Vanilla-Chocolate b)Sequence the jobs using EDD rule. Time Flavor Required Due Date Vanilla 4 days 3* stop. Reject vanilla,then the new sequence is: Time Flavor Required Due Date Strawberry 2 days 6 Chocolate 7 days 8 Peanut 9 days 12 No more tardy jobs. Hence,the number of tardy jobs 1. Answers4 20 Att. Att. Total Month Belts(#)Belts(hrs) Hand(#)Hand(hrs) Case#Case(hrs)Hrs. 2500 5000 1250 3750 240 1440 10190 2 2800 5600 680 2040 380 2280 9920 心 2000 4000 1625 4875 110 660 9535 4 3400 6800 745 2235 75 450 9485 夕 3000 6000 835 2505 126 756 9261 6 1600 3200 375 1125 45 270 4595 b) Cum Cum Min. Working Working Working Demand Workforce Month Days Hours Hours Hours (Ratio) 1 22 154 154 10190 67 20 140 294 20110 69 3 19 133 427 29645 70 4 24 168 595 39130 66 5 21 147 742 48391 66 6 17 119 861 52986 62 Hence the minimum constant work force size is 70.It is probably not advantageous to bring the work force level up to 70 workers.The excess demand can be absorbed by overtime or by employing part-time workers. The firm can be more flexible by keeping the number of full-time employees to a minimum. c)If a plan is to utilize only regular time employees,then excess demand must be absorbed by overtime.Since there are 46 employees with the firm,we obtain (A) (B) (C=46*B) (D) (E=D-C) Working Regular Required Overtime Month Hours Hours Hours Hours 1 154 7084 10,190 3106 2 140 6440 9,920 3408 3 133 6118 9,535 3417 4 168 7728 9,485 1757 5 147 6762 9,261 2499Strawberry 2 days 6 Peanut 2 days 12 a) SPT rule minimizes the mean flow time. The optimal sequence is Strawberry-Peanut-Vanilla-Chocolate or Peanut-Strawberry-Vanilla-Chocolate b) Sequence the jobs using EDD rule. Time Flavor Required Due Date Vanilla 4 days 3 * Stop. Reject vanilla, then the new sequence is: Time Flavor Required Due Date Strawberry 2 days 6 Chocolate 7 days 8 Peanut 9 days 12 No more tardy jobs. Hence, the number of tardy jobs = 1. Answers4 20’ Att. Att. Total Month Belts(#) Belts(hrs) Hand(#) Hand(hrs) Case# Case(hrs) Hrs. 1 2500 5000 1250 3750 240 1440 10190 2 2800 5600 680 2040 380 2280 9920 3 2000 4000 1625 4875 110 660 9535 4 3400 6800 745 2235 75 450 9485 5 3000 6000 835 2505 126 756 9261 6 1600 3200 375 1125 45 270 4595 b) Cum Cum Min. Working Working Working Demand Workforce Month Days Hours Hours Hours (Ratio) 1 22 154 154 10190 67 2 20 140 294 20110 69 3 19 133 427 29645 70 4 24 168 595 39130 66 5 21 147 742 48391 66 6 17 119 861 52986 62 Hence the minimum constant work force size is 70. It is probably not advantageous to bring the work force level up to 70 workers. The excess demand can be absorbed by overtime or by employing part-time workers. The firm can be more flexible by keeping the number of full-time employees to a minimum. c) If a plan is to utilize only regular time employees, then excess demand must be absorbed by overtime. Since there are 46 employees with the firm, we obtain (A) (B) (C=46*B) (D) (E=D-C) Working Regular Required Overtime Month Hours Hours Hours Hours 1 154 7084 10,190 3106 2 140 6440 9,920 3408 3 133 6118 9,535 3417 4 168 7728 9,485 1757 5 147 6762 9,261 2499