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1 George Walker has compiled the following table of six items in inventory along with the unit cost and the annual demand In units Identification Code XXI B66 3CPO 33CP R2D2 RMS Total Unit Cost ($) Annual Demand in Units 1,200 1,110 896 1,104 1,110 961 Total %

5.84 5.40 1.12 74.54 2.00 2.08

12.2 Borekeri Enterprise has the following 10 items in inventory. Theodore Boreki asks you, a recent OM graduate, to divide these items into ABC classification. What do you report back? Identification Code A2 B8 C7 D1 E9 F3 G2 H2 I5 J8 Total Annual Demand in Units 3,000 4,000 1,500 6,000 1,000 500 300 600 1,750 2,500

Unit Cost ($) $50 12 45 10 20 500 1,500 20 10 5


12.4 Howard Electronics, a small manufacturer of electronic research equipment, has approximately 7,000 items in its inventory and has hired Joan Paul to manage its inventory. He has determined that:

12.5 William Bevilles computer training school, in Richmond, stocks with the following characteristics: a) Calculate the EOQ for workbooks? b) What are the annual holding costs for the workbooks? c) What are the annual ordering costs?

12.6 If D= 8,000 per month, S=$45 per order, and H= $2 per unit per month, what is the economic order quantity?

12.7 Henry Crouchs law office has traditionally ordered ink refills 60 units at a time. The firm estimates that carrying cost is 40% of the $10 unit cost and the annual demand is about 240 units per year. What value of ordering cost would its action be optimal?

12.8 Madeline Thimmes Dream Store sells water beds and assorted supplies. Her best-selling bed has an annual demand of 400 units, ordering cost is $40 and holding cost is 5% per unit per year. a) How many units should be ordered each time and order is placed? b) If the Holding cost per unit was $6 instead of $5, what would the optimal order quantity be?

12.9 Southeastern Bell stocks a certain switch connector at its central warehouse for supplying field service offices. The yearly demand for these connectors is 15,000 units. Southeastern estimates its annual holding cost for this item to be $25 per unit. The cost to place and process an order from the supplier is 8 working days. a) b) c) d) Find the economic order quantity Find the annual holding cost Find the annual ordering costs What is the reorder point?

12.10 Lead time for one of your fastest moving products is 21 days. Demand during this period averages 100 units per day. What would be an appropriate reorder point?

12.11 Annual demand for the notebook binders at Ducans Stationary Shop is 10,000 units. Dana Duncan operates her business 300 days per year and finds that deliveries from her supplier generally take 5 working days. Calculate the reorder point for the notebook binders that she stocks.

12.12. - Marilyn Hart is the purchasing agent for Central Valve Company, which sells industrial valves and fluid control devices. The annual demand is 4,000 units. The cost of each valve is $90, and the inventory carrying cost is $9, Marilyn has made a study of the costs involved in placing an order for any of the valves that Central stocks, the average ordering cost is $25 per order. Furthermore, it takes about 5 working days for an order to arrive from the supplier. The demand per week is 80. a) b) c) d) What is the economic order quantity? What is the average inventory if the economic order quantity? What is the optimal number of orders per year? What is the optimal number of days between any two orders, assuming 250 working days per year? e) What is the total annual inventory cost? f) What is the reorder point?

12.13. - Joe Henrys machine shop uses 2,500 brackets during the course of a year. Theses brackets are purchased from a supplier 90 miles away. The following information is known about the brackets: a) b) c) d) e) f) What would be the economic order quantity? What would be the average inventory? What would be the annual inventory holding cost? How many orders would be made each year? What would be the annual order cost? What is the reorder point?

12.14 Myriah Fitzgibbon uses 1,200 of a certain spare part that costs $25 for each order with an annual holding cost of $24 Calculate the total cost for order sizes of 25, 40, 50, 50, and 100. Identify the economic order quantity and consider the implications for making an error in calculating order quantity

12.15 M. Cotteler Electronics supplies microcomputer circuitry to a company that incorporates microprocessors into refrigerators and other home appliances. The annual demand of one of the components is 250 units, carrying cost is estimated to be $1 per unit per year, and the ordering cost is $20 per order a) b) c) d) How many units should be ordered each time an order is placed? How many orders per year are needed with the optimal policy? What is the average inventory if costs are minimized? Suppose that the ordering costs are not $20, and Pattersson has been ordering 150 units each time. Determine what the ordering cost would have to be?

12.16 Bruce Woodworths company produces a product for which annual demand is 10,000. Because it operates 200 days per year, demand is about 50 per day. Daily production is 200 units. Holding cost is $1 per unit per year; setup cost is $200. If you wish to produce this product in batches, what size batch should be used?

12.17 Redovilsky Manufacturing Company, in Hayward makes flashing lights for toys. The company operates in production facility 300 days per year. It has orders for about 12,000 flashing lights per year and has the capability of producing 100 per day. Setting up the light production costs $50. The cost of each light is $1. The holding cost is $0.10 per light per year. a) b) c) d) What is the optimal size of production run? What is the average holding cost per year? What is the average setup cost per year? What is the total cost per year, including the cost of the lights?

12.18 Meiners is the production manager of Wheel- Rite, a small producer of metal parts. Wheel- Rite supplies Caltex. A larger assembly, with 10,000 wheel bearings each year. Setup cost for Wheel is $40 and holding cost is $.60 per wheel per year. Wheel-Rite can produce 500 wheel bearings per day. Cal-Tex is a just in time manufacturer and requires that 50 bearings be shipped to it each business day. a) b) c) d) What is the optimum production quantity? What is the maximum number of wheel bearings that will be in inventory at Wheel? How many production runs of wheel bearings will Wheel-Rite have in a year]? What are the Total Setup + Holding cost for Wheel- Rite?

12.19. Cesar Rogo a Mississippi chain of computer hardware and software retail outlets, supplies both educational and commercial customers with memory ans storage devices. It currently faces the following ordering decision relating to purchases of CD-ROMs.

12.20 McLeavey Manufacturing has a demand for 1,000 pumps each year. The cost of a pump is $50. It costs Mc Leavey $40 to place an order, and carrying costs is 25% of unit cost. If pumps are ordered in quantities of 200, McLeavey can get a 3% discount. Should it order 200 pumps at time and take the 3% discount?

12.21 Wang Distributors has an annual demand for an airport metal detector of 1,400 units. The cost of a typical detector to Wang is $400. Carrying cost is estimated to be 20% of the unit cost, and ordering cost is $25 per order. If Ping Wang, the owner, orders in quantities of 300 or more, he can get a 5% discount on the cost of the detectors. Should Wang take the quantity discount?

12.22 The regular price of a DVD component is $20. On orders of $75 units or more, the price is discounted to $18.50. On orders of 100 units or more, the discount price is 415.75. At present, Sound Business, Inc., a manufacturer of hight fidelity components, has an inventory carrying costs of 5% per unit per year, and its ordering cost }410. Annual demand is 45 components. What should Sound Business, Inc. do?

12.23 Rocky Mountain sells 20,000 tires of a particular type per year. The ordering costs for each order are $40, and the holding cost is 20%of the purchase price of the tires per year. The purchase price is $20 per tire if fewer than 500 tires are ordered, $18 per tire if 500 or more, but fewer than 1,000 tires are ordered and $17 per tire if 1,000 or more tires are ordered. How many tires should Rocky order each time?

12.24 Van Oyen has gone out on bid for a regulator component. The demand is 700 units per month. The item can be purchased from either Allen Manufacturing or Baker Manufacturing. Ordering cost is $50, an annual holding cost is $5 ALLEN MFG Quantity 1-499 500-999 1,000 + Unit Orice 16 15.50 15.00 BAKER MFG Quantity 1-399 400-799 800 + Unit Price 16.10 15.60 15.10

12.25 Cris Dandving Irrigation, Inc has summarized the price list from four potential suppliers of an underground control valve. Annual usage is 2,400 valves, order cost is $10 per order; and annual inventory holding costs are $3.33 per unit Vendor A Quantity Price 1-49 $35 50-74 34.75 75-149 33.55 150-299 32.35 300-499 31.15 500 + 30.75 Vendor B Quantity Price 1-74 $34.75 75-149 34.00 150-299 32.80 300-499 31.60 500 + 30.50 Vendor C Quantity Price 1-99 $34-50 100-199 33.75 200-399 32.50 400-+ 31.10 Vendor D Quantity Price 1-199 $34.25 200-399 33,00 400 + 31.00

12.26 Emercy Pharmaceutical uses an unstable chemical compound that must be kept in an environment where both temperature and humidity can be controlled. Emeryt uses 800 pounds per month of the chemical, estimates the holding cost to be 50% of the purchase, the order cost is $50 per order. VENDOR 1 Quantity 1-499 500-999 1,000 + Unit Orice $17.00 16.75 16.50 Quantity 1-399 400-799 800 + 1199 1,200 + VENDOR 2 Unit Price $17.10 16.85 16.60 16.25

a) b) c) d)

What is the economic order quantity for both suppliers? What quantity should be ordered and which supplier should be used? What is the total cost for the most economic order size? What factors should be considered besides total cost?

Daria Marlene Rodrguez Olvera

Supply Chain Management

Teacher: Hiemy Shu Lara

Problems Inventory and Production

Aguascalientes, Ags. 01 de noviembre del 2012