SOLVED

17) Thomas’ Bike Shop stocks a high volume item that has a normally distributed demand during lead time. The average daily demand is 70 units, the lead time is 4 days, and the standard deviation of demand during lead time is 15. a. How much safety stock provides a 95% service level to Thomas? b. What should the reorder point be? 18) The new office supply discounter, Paper Clips, Etc. (PCE), sells a certain type of ergonomically correct office chair that costs $300. The annual holding cost rate is 40% of the item cost, annual demand is 900 units, and the ordering cost is $20 per order. The lead time is 4 days. Because demand is variable (standard deviation of daily demand is 2.4 chairs), PCE has decided to establish a customer service level of 90%. The store is open 300 days per year. a. What is the optimal order quantity? b. What is the safety stock? c. What is the reorder point? 19) Huckaby Motor Services, Inc. rebuilds small electrical items such as motors, alternators, and transformers, all using a certain type of copper wire. The firm’s demand for this wire is approximately normal, averaging 20 spools per week, with a standard deviation of 6 spools per week. Cost per spool is $24; ordering costs are $25 per order; inventory handling cost is $4.00 per spool per year. Acquisition lead time is four weeks. The company works 50, 5-day weeks per year. a. What is the optimal size of an order, if minimization of inventory system cost is the objective? b. What are the safety stock and reorder point if the desired service level is 90%? a. Q* = = 111.8Huckaby should order 112 spools at one time. b. SS = 1.28 × 6 × = 15.36 or about 15 spools. The ROP is thus 20(4) + 15 = 95 spools. 20) Demand for ice cream at the Ouachita Dairy can be approximated by a normal distribution with a mean of 47 gallons per day and a standard deviation of 8 gallons per day. The new management desires a service level of 95%. Lead time is four days; the dairy is open seven days a week. What reorder point would be consistent with the desired service level? 21) The Winfield Distributing Company has maintained an 80% service level policy for inventory of string trimmers. Mean demand during lead time is 170 trimmers, and the standard deviation during lead time is 60 trimmers. The annual cost of carrying one trimmer in inventory is $6. The area sales people have recently told Winfield’s management that they could expect a $400 improvement in profit (based on current figures of cost per trimmer) if the service level were increased to 99%. Is it worthwhile for Winfield to make this change?