上海交通大学试卷（A卷) (2010至2011学年第1学期) 班级号 学号 姓名 课程名称Production and Operations Analysis 成绩 1.A simple forecasting method for weekly sales of DVD derives used by a local computer dealer is to form the average of the two most recent sales figures.Suppose sales for the drives for the past 7 weeks were Week 1 2 3456 7 Sales8675728313265110 a. Determine the one-step-ahead forecasts made for periods 3 through 7 using this method. b.Determine the forecast errors for these periods c.Compute the MAD,the MSE,and the MAPE based on the forecast errors computed in part(b). 2.A specialty coffeehouse sells Colombian coffee at a fairly steady rate of 280 pounds annually The beans are purchased from a local supplier for $2.40 per pound.The coffeehouse estimates that it costs $45 in paperwork and labor to place an order for the coffee,and holding costs are based on a 20 percent annual interest rate. a. Determine the optimal order quantity for Colombian coffee b.What is the time between placements of orders? c. What is the average annual cost of holding and setup due to this item? d.If replenishment lead time is three weeks,determine the reorder level based on the on-hand inventory 3. Billy's Bakery bakes fresh bagels each morning.The daily demand for bagels is a random variable with a distribution estimated from prior experience given by Number of Bagels 0 5 10 1520 30 35 Sold in One Day 25 Probability .05.10.10.20.25.15 .10 .05 The bagels cost Billy's 8 cents to make,and they are sold for 35 cents each.Bagels unsold at the end of the day are purchased by a nearby charity soup kitchen for 3 cents each. a. Based on the given discrete distribution,how many bagels should Billy's bake at the start of each day?(Your answer should be a multiple of 5.) b.If you were to approximate the discrete distribution with a normal distribution,would you expect the resulting solution to be close to the answer that you obtained in part(a)?Why or why not? C. Determine the optimal number of bagels to bake each day using a normal approximation.(Hint: You must compute the mean and the variance o2 of the demand from the given discrete distribution.) A卷总2页第页A 卷 总 2 页 第 页 上 海 交 通 大 学 试 卷（ A 卷） （ 2010 至 2011 学年 第 1 学期 ） 班级号____________ 学号 ______________________ 姓名 __ 课程名称 Production and Operations Analysis 成绩 ___ 1. A simple forecasting method for weekly sales of DVD derives used by a local computer dealer is to form the average of the two most recent sales figures. Suppose sales for the drives for the past 7 weeks were Week 1 2 3 4 5 6 7 Sales 86 75 72 83 132 65 110 a. Determine the one-step-ahead forecasts made for periods 3 through 7 using this method. b. Determine the forecast errors for these periods c. Compute the MAD, the MSE, and the MAPE based on the forecast errors computed in part (b). 2. A specialty coffeehouse sells Colombian coffee at a fairly steady rate of 280 pounds annually. The beans are purchased from a local supplier for $2.40 per pound. The coffeehouse estimates that it costs $45 in paperwork and labor to place an order for the coffee, and holding costs are based on a 20 percent annual interest rate. a. Determine the optimal order quantity for Colombian coffee. b. What is the time between placements of orders? c. What is the average annual cost of holding and setup due to this item? d. If replenishment lead time is three weeks, determine the reorder level based on the on-hand inventory. 3. Billy’s Bakery bakes fresh bagels each morning. The daily demand for bagels is a random variable with a distribution estimated from prior experience given by Number of Bagels Sold in One Day 0 5 10 15 20 25 30 35 Probability .05 .10 .10 .20 .25 .15 .10 .05 The bagels cost Billy’s 8 cents to make, and they are sold for 35 cents each. Bagels unsold at the end of the day are purchased by a nearby charity soup kitchen for 3 cents each. a. Based on the given discrete distribution, how many bagels should Billy’s bake at the start of each day? (Your answer should be a multiple of 5.) b. If you were to approximate the discrete distribution with a normal distribution, would you expect the resulting solution to be close to the answer that you obtained in part (a)? Why or why not? c. Determine the optimal number of bagels to bake each day using a normal approximation. (Hint: You must compute the mean  and the variance 2  of the demand from the given discrete distribution.)