Operations Management
13th Edition
ISBN: 9781259667473
Author: William J Stevenson
Publisher: McGraw-Hill Education
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Chapter 3, Problem 17P
A pharmacist has been monitoring sales of 2 certain over-the-counter pain reliever. Daily sales during the last 15 days were as follows:
a. Which method would you suggest using to predict future sales—a linear trend equation ox trend-adjusted exponential smoothing? Why?
b. If you learn that on tome days the store ran out of the specific pain reliever, would that knowledge cause you any concern? Explain?
c. Assume that the data refer to demand rather than sales. Using trend-adjusted smoothing with an initial
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A pharmacist has been monitoring sales of a certain over-the-counter pain reliever. Daily sales duringthe last 15 days wereDay: 1 2 3 4 5 6 7 8 9Number sold: 36 38 42 44 48 49 50 49 52Day: 10 11 12 13 14 15Number sold: 48 52 55 54 56 57a. Using linear trend equation method, predict future sales from the given data.b. If you learn that on some days the store ran out of the specific pain reliever, would that knowledge cause you any concern? Explain.
3. Quarterly sales of a car dealer exhibit an almost constant mean over time, but sales fluctuate
depending on the quarter of the year (exhibits seasonality).
Quarter
Q1 - Spring
Q2 - Summer
Q3 - Fall
Q4 - Winter
Mean
Year 1
32
74
53
22
45.25
Year 2
30
71
63
15
44.75
Year 3
35
83
45
19
45.5
(a) Using three years' worth of quarterly data that is provided, develop a set of seasonal factors that
could be used to forecast car sales
(b) Forecast car sales in each of the four quarters (Q1-Q4) of the following year (Year 4), using these
seasonal factors.
The following table gives the number of pints of type A blood used at Damascus Hospital in the past 6 weeks:
a) The forecasted demand for the week of October 12 using a 3-week moving average =
Week Of
August 31
September 7
September 14
September 21
September 28
October 5
pints (round your response to two decimal places).
Pints Used
345
389
408
381
371
374
Chapter 3 Solutions
Operations Management
Ch. 3.15 - Prob. 1.1RQCh. 3.15 - Prob. 1.2RQCh. 3.15 - Prob. 1.3RQCh. 3 - What are the main advantage that quantitative...Ch. 3 - What are some of the consequences of poor...Ch. 3 - List the specific weaknesses of each of these...Ch. 3 - Forecasts are generally wrong a. Why are forecasts...Ch. 3 - What is the purpose of establishing control limits...Ch. 3 - What factors would you consider in deciding...Ch. 3 - Contrast the use of MAD and MSE in evaluating...
Ch. 3 - What advantages as a forecasting tool does...Ch. 3 - How does the number of periods in a moving average...Ch. 3 - What factors enter into the choice of a value for...Ch. 3 - Prob. 11DRQCh. 3 - Explain how using a centered moving average with a...Ch. 3 - Contrast the terms sales and demand.Ch. 3 - Contrast the reactive and proactive approaches to...Ch. 3 - Explain how flexibility in production systems...Ch. 3 - How is forecasting in the context of a supply...Ch. 3 - Which type of forecasting approach, qualitative or...Ch. 3 - Prob. 18DRQCh. 3 - Choose the type of forecasting technique (survey,...Ch. 3 - Explain the trade-off between responsiveness and...Ch. 3 - Who needs to be involved in preparing forecasts?Ch. 3 - How has technology had an impact on forecasting?Ch. 3 - It has been said that forecasting using...Ch. 3 - What capability would an organization have to have...Ch. 3 - When a new business is started, or a patent idea...Ch. 3 - Discuss how you would manage a poor forecast.Ch. 3 - Omar has beard from some of his customers that...Ch. 3 - Give three examples of unethical conduct involving...Ch. 3 - A commercial baker, has recorded sales (in dozens)...Ch. 3 - National Scan, Inc., sells radio frequency...Ch. 3 - A dry cleaner uses exponential smoothing to...Ch. 3 - An electrical contractors records during the last...Ch. 3 - A cosmetics manufacturer s marketing department...Ch. 3 - Prob. 6PCh. 3 - Freight car loadings ova a 12-year period at a...Ch. 3 - Air travel on Mountain Airline for the past 18...Ch. 3 - a. Obtain the linear trend equation for the...Ch. 3 - After plotting demand for four periods, an...Ch. 3 - A manager of a store that sells and installs spas...Ch. 3 - The following equation summarizes the trend...Ch. 3 - Compute seasonal relatives for this data the SA...Ch. 3 - A tourist center is open on weekends (Friday,...Ch. 3 - The manager of a fashionable restaurant open...Ch. 3 - Obtain estimates of daily relatives for the number...Ch. 3 - A pharmacist has been monitoring sales of 2...Ch. 3 - New car sales for a dealer in Cook County,...Ch. 3 - The following table shows a tool and die companys...Ch. 3 - An analyst must decide between two different...Ch. 3 - Two different forecasting techniques (F1 and F2)...Ch. 3 - Two independent methods of forecasting based on...Ch. 3 - Long-Life Insurance has developed a linear model...Ch. 3 - Timely Transport provides local delivery service...Ch. 3 - The manager of a seafood restaurant was asked to...Ch. 3 - The following data were collected during a study...Ch. 3 - Lovely Lawns Inc., intends to use sales of lawn...Ch. 3 - The manager of a travel agency has been using a...Ch. 3 - Refer to the data in problem 22 a. Compute a...Ch. 3 - The classified department of a monthly magazine...Ch. 3 - A textbook publishing company has compiled data on...Ch. 3 - A manager has just receded an valuation from an...Ch. 3 - A manager uses this equation to predict demand for...Ch. 3 - A manager uses a trend equation plus quarterly...Ch. 3 - ML MANUFACTURING ML Manufacturing makes various...Ch. 3 - ML MANUFACTURING ML Manufacturing makes various...Ch. 3 - HIGHLINE FINANCIAL SERVICES, LTD. Highline...
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