Aggregate Pl... QU AA . en generating an aggregate plan, the operations manager must answer several estions: 1. Should inventories be used to absorb changes in demand during the planning period? 2. Should changes be accommodated by varying the size of the workforce? 3. Should part-timers be used, or should overtime and idle time absorb fluctuations? 4. Should subcontractors be used on fluctuating orders so a stable workforce can be maintained? 5. Should prices or other factors be changed to influence demand? of these are legitimate planning strategies. They involve the manipulation of wentory, production rates, labor levels, capacity, and other controllable variables. We Ell now examine eight options in more detail. The first five are called capacity options Under ideal conditions, a service bay at a Fast Lube can serve 6 cars per hour. The effective capacity and efficiency of a Fast Lube service bay are known to be 5.5 and 0.880, respectively. What is the minimum number of service bays Fast Lube needs to achieve an anticipated servicing of 200 cars per 8-hour day? 13.4 Using the information in Problem 13.30, develop plan B. Produce at a constant rate of 1,400 units per month, which will meet minimum demands. Then use subcontracting, with additional units at a premium price of $75 per unit. Evaluate this plan by computing the costs for January through August