Seabreeze Furniture in Orlando maintains a large, central warehouse where it stores items until they are sold or needed by the company’s many stores in the Central Florida area. A four-person crew works at the warehouse to load or unload trucks that arrive at the warehouse at a rate of one per hour (with exponentially distributed interarrival times). The time it takes the crew to unload each truck follows an exponential distribution with a mean service rate of 4 trucks per hour. Each worker costs the company $21 per hour in wages and benefits. Seabreeze’s management is currently trying to cut costs and is considering reducing the number of workers on this warehouse crew. They believe three workers would be able to provide a service rate of 3 trucks per hour, two workers a service rate of 2 trucks per hour, and one worker a service rate of 1 truck per hour. The company estimates it costs $35 for each hour a truck spends at the loading dock (whether it is waiting for service or being loaded or unloaded). a. Should Seabreeze ever consider having just one worker on the crew? Explain your answer. b. For each possible crew size, determine the expected queue length, expected total time in the system, the probability that a customer waits, and the total hourly cost. c. What crew size would you recommend?
> How would you define the words description, prediction, and prescription? Carefully consider what is unique about the meaning of each word.
> In what ways are prescriptive models different from descriptive models?
> What is an independent variable?
> What is a dependent variable?
> What are the benefits of using a modeling approach to decision making?
> In what ways do spreadsheet models facilitate the decision-making process?
> What is the relationship between business analytics and spreadsheet modeling?
> Of the queuing configurations shown in Figure 13.2, which would you prefer to wait in? Explain your response. Figure 13.2 Customer Customer ... Arrives Leaves Waiting Line Server Customer Leaves Server 1 Customer Customer ... Arrives Leaves Waiting
> Define the term business analytics.
> What is the difference between a spreadsheet model and a computer model?
> Define the term computer model.
> Sanderson Manufacturing produces ornate, decorative wood frame doors and windows. Each item produced goes through three manufacturing processes: cutting, sanding, and finishing. Each door produced requires 1 hour in cutting, 30 minutes in sanding, and 30
> A farmer in Georgia has a 100-acre farm on which to plant watermelons and cantaloupes. Every acre planted with watermelons requires 50 gallons of water per day and must be prepared for planting with 20 pounds of fertilizer. Every acre planted with cantal
> The Quality Desk Company makes two types of computer desks from laminated particle board. The Presidential model requires 30 square feet of particle board, 1 keyboard sliding mechanism, 5 hours of labor to fabricate, and sells for $149. The Senator model
> Zippy motorcycle manufacturing produces two popular pocket bikes (miniature motorcycles with 49cc engines): the Razor and the Zoomer. In the coming week the manufacturer wants to produce up to 700 bikes and wants to ensure the number of Razors produced d
> Blacktop Refining extracts minerals from ore mined at two different sites in Montana. Each ton of ore type 1 contains 20% copper, 20% zinc, and 15% magnesium. Each ton of ore type 2 contains 30% copper, 25% zinc, and 10% magnesium. Ore type 1 costs $90 p
> The marketing manager for Mountain Mist soda needs to decide how many TV spots and magazine ads to run during the next quarter. Each TV spot costs $5,000 and is expected to increase sales by 300,000 cans. Each magazine ad costs $2,000 and is expected to
> American Auto is evaluating their marketing plan for the sedans, SUVs, and trucks they produce. A TV ad featuring this SUV has been developed. The company estimates each showing of this commercial will cost $500,000 and increase sales of SUVs by 3% but r
> Which of the following constraints are not linear or cannot be included as a constraint in a linear programming problem? a. 2X1 + X2 – 3X3 ≥ 50 b. 2X1 + √X2 ≥ 60 c. 4X1 – 1/3X2 = 75 d. 3X1 + 2X2 - 3X3 / X1 + X2 + X3 ≤ 0.9 e. 3X21 + 7X2 ≤ 45
> Bill’s Grill is a popular college restaurant that is famous for its hamburgers. The owner of the restaurant, Bill, mixes fresh ground beef and pork with a secret ingredient to make delicious quarter-pound hamburgers that are advertised as having no more
> Refer to the previous question. Suppose that Electrotech’s management decides that they need to make at least 20 generators and at least 20 alternators. In Previous Question: The Electrotech Corporation manufactures two industrial-sized electrical devic
> The Electrotech Corporation manufactures two industrial-sized electrical devices: generators and alternators. Both of these products require wiring and testing during the assembly process. Each generator requires 2 hours of wiring and 1 hour of testing a
> The Gourmet Grill Company manufactures and sells two different types of grills: propane and electric. Each propane grill sells for $320 and costs $220 to manufacture. Each electric grill sells for $260 and costs $180 to manufacture. Each grill goes throu
> Oakton Manufacturing makes two types of rocking chairs specifically designed for men and women known as the His and Hers models. Each chair requires four legs and two rockers but differing numbers of wooden dowels. Each His chair requires four short dowe
> Bibbins Manufacturing produces softball and baseballs for youth recreation leagues. Each softball costs $11 to produce and sells for $17 while each baseball costs $10.50 and sells for $15. The material and labor required to produce each item is listed he
> Solve the following LP problem graphically by enumerating the corner points. MAX: 10X1 + 12X2 Subject to: 8X1 + 6X2 ≤ 98 6X1 + 8X2 ≤ 98 X1 + X2 ≥ 14 X1, X2 ≥ 0
> Solve the following LP problem using level curves. MAX: 4X1 + 5X2 Subject to: 2X1 + 3X2 ≤ 120 4X1 + 3X2 ≤ 140 X1 + X2 ≥ 80 X1, X2 ≥ 0
> Solve the following LP problem graphically using level curves. MIN: 2X1 + 3X2 Subject to: 2X1 + 1X2 ≥ 3 4X1 + 5X2 ≥ 20 2X1 + 8X2 ≥ 16 5X1 + 6X2 ≤ 60 X1, X2 ≤ 0
> Consider the following LP problem. MAX: 3X1 + 2X2 Subject to: 3X1 + 3X2 ≤ 300 6X1 + 3X2 ≤ 480 3X1 + 3X2 ≤ 480 X1, X2 ≥ 0 a. Sketch the feasible region for this model. b. What is the optimal solution? c. Identify any redundant constraints in this model.
> Are the following objective functions for an LP model equivalent? That is, if they are both used, one at a time, to solve a problem with exactly the same constraints, will the optimal values for X1 and X2 be the same in both cases? Why or why not? MAX: 2
> Solve the following LP problem graphically by enumerating the corner points. MIN: 5X1 + 20X2 Subject to: X1 + X2 ≥ 12 2X1 + 5X2 ≥ 40 X1 + X2 ≤ 15 X1, X2 ≥ 0
> Solve the following LP problem graphically using level curves. MAX: 2X1 + 5X2 Subject to: 6X1 + 5X2 ≤ 60 2X1 + 3X2 ≤ 24 3X1 + 6X2 ≤ 48 X1, X2 ≥ 0
> Solve the following LP problem graphically by enumerating the corner points. MAX: 3X1 + 4X2 Subject to: X1 ≤ 12 X2 ≤ 10 4X1 + 6X2 ≤ 72 X1, X2 ≥ 0
> An LP model can have more than one optimal solution. Is it possible for an LP model to have exactly two optimal solutions? Why or why not?
> PC-Express is a computer retail store that sells desktops and laptops. The company earns $600 on each desktop computer it sells and $900 on each laptop. The computers PC-Express sells are actually manufactured by another company. This manufacturer has a
> The owner of Blue Ridge Hot Tubs, Howie Jones, has asked for your assistance analyzing how the feasible region and solution to his production problem might change in response to changes in various parameters in the LP model. He is hoping this might furth
> Vacations Inc. (VI) markets time-share condominiums throughout North America. One way the company generates sales leads is by offering a chance to win a free mini-vacation to anyone who fills out an information card and places it in boxes VI has distribu
> Bullseye department store is a discount retailer of general merchandise in the southeastern United States. The company owns more than 50 stores in Florida, Georgia, South Carolina, and Tennessee that are serviced by the company’s main warehouse near Stat
> DeColores Paint Company owns 10 trucks that it uses to deliver paint and decorating supplies to builders. On average, each truck returns to the company’s single loading dock at a rate of three times per 8-hour day (or at a rate of 3/8 = 0.375 times per h
> A manufacturer of engine belts uses multipurpose manufacturing equipment to produce a variety of products. A technician is employed to perform the setup operations needed to change the machines over from one product to the next. The amount of time requir
> To determine the feasible region associated with less than or equal to constraints or greater than or equal to constraints, we graphed these constraints as if they were equal to constraints. Why is this possible?
> Several hundred PCs are in use at the corporate headquarters for National Insurance Corporation. The pattern of breakdowns for these PCs follows a Poisson distribution with an average rate of 4.5 breakdowns per 5-day work week. The company has a repair t
> Refer to the previous question. Suppose that Road Rambler’s phone system can only keep four calls on hold at any time, the average profit margin of each call is $55, and sales reps cost the company $12 per hour. In Previous Question Road Rambler sells s
> During tax season, the IRS hires seasonal workers to help answer the questions of taxpayers who call a special 800 telephone number for tax information. Suppose that calls to this line occur at a rate of 60 per hour and follow a Poisson distribution. The
> State University allows students and faculty to access its super computer by high-speed proxy servers. The university has 15 proxy server connections that can be used. When all of the proxy server connections are in use, the system can keep up to 10 user
> The Orange Blossom Marathon takes place in Orlando, Florida, each December. The organizers of this race are trying to solve a problem that occurs at the finish line each year. Thousands of runners take part in this race. The fastest runners finish the 26
> The Westland Title Insurance Company leases one copying machine for $45 per day that is used by all individuals at their office. An average of five persons per hour arrive to use this machine, with each person using it for an average of 8 minutes. Assume
> The manager of the Radford Credit Union (RCU) wants to determine how many part-time tellers to employ to cover the peak demand time in its lobby from 11:00 a.m. to 2:00 p.m. RCU currently has three full-time tellers that handle the demand during the rest
> The Madrid Mist outlet store at Chiswell Mills sells discount luggage and does most of its daily business in the evening between the hours of 6 and 9 pm. During this time, customers arrive at the checkout desk at a rate of one every 2 minutes following a
> On Friday nights, patients arrive at the emergency room at Mercy Hospital following a Poisson distribution at an average rate of seven per hour. Assume that an emergency-room physician can treat an average of three patients per hour, and that the treatme
> In the solution to the Blue Ridge Hot Tubs problem, the optimal values for X1 and X2 turned out to be integers (whole numbers). Is this a general property of the solutions to LP problems? In other words, will the solution to an LP problem always consist
> Cuts-R-Us provides low cost haircuts at a shopping center in Boise, Idaho. During the day, customers arrive at an average rate of 9 per hour following an exponential distribution. After a customer is in a cosmetician’s chair, it takes an average of 18 mi
> Tri-Cities Bank has a single drive-in teller window. On Friday mornings, customers arrive at the drive-in window randomly, following a Poisson distribution at an average rate of 30 per hour. a. How many customers arrive per minute, on average? b. How man
> Describe a situation in which a business might want customers to wait some amount of time before receiving service.
> This chapter implies that customers find waiting in line to be an unpleasant experience. In addition to reducing the length of the wait itself, what other steps could a business take to reduce the frustration customers experience while waiting? Give spec
> Consider the three queuing configurations shown in Figure 13.2. For each configuration, describe a situation (besides the examples mentioned in the chapter) in which you have encountered or observed the same type of queuing system. Figure 13.2 Custo
> Calls arrive at a rate of 150 per hour to the 800 number for the Land’s Beginning mail-order catalog company. The company currently employs 20 operators who are paid $10 per hour in wages and benefits and can each handle an average of 6 calls per hour. A
> The drive-thru window at Hokie Burger requires 2.5 minutes on average to process an order with a standard deviation of 3 minutes. Cars arrive at the window at a rate of 20 per hour. a. On average, how many cars are waiting to be served? b. On average, ho
> Interstate 81 through southwest Virginia is heavily traveled by long-distance truckers. To cut down on accidents, The Virginia State Patrol carries out random inspections of a trucks weight and the condition of its brakes. On Fridays, trucks approach the
> Road Rambler sells specialty running shoes and apparel through catalogs and the Web. Customers can phone in orders at any time day or night, 7 days a week. During the 4 a.m. to 8 a.m. shift, a single sales rep handles all calls. During this time, calls a
> Customers checking out at Food Tiger arrive in a single-line queue served by two cashiers at a rate of eight per hour according to a Poisson distribution. Each cashier processes customers at a rate of eight per hour according to an exponential distributi
> Patrick’s luck had changed overnight – but not his skill at mathematical reasoning. The day after graduating from college he used the $20 that his grandmother had given him as a graduation gift to buy a lottery ticket. He knew his chances of winning the
> During the summer of 2006, a syndicate of investors led by The Blackstone Group, one of Wall Street’s largest private equity investment firms, initiated a secret plan to acquire Freescale Semiconductor. Based in Austin, Texas, Freescale was among the wor
> Suzette Washington financed her college education by working as an inventory clerk for Bertolini’s, a clothing store chain located in the southeastern United States. 1 Bertolini’s caters primarily to fashion-conscious young men and women. The company’s
> Alex Fries emigrated to the United States from Germany in the early nineteenth century. 1 The excitement and opportunity promised by the western frontier fascinated thousands of new Americans, including the young German, who followed his dreams and the
> Imagine this scenario. A few years after graduating from the University of Miami, New Mexico State University, or Ohio Wesleyan University with an accounting degree, you find yourself working as an audit senior with an international accounting firm. Your
> Sam Walton was born on March 29, 1918, in Kingfisher, Oklahoma, a small town 50 miles northwest of Oklahoma City. Sam’s father, a farmer, struggled to support his family during the Great Depression. The Walton family hopscotched around the country before
> A Japanese bank introduced the concept of around-the-clock access to cash in the 1960s when it installed the world’s first cash-dispensing machine. In 1968, the first networked ATM appeared in Dallas, Texas. 1 Two generations later, there are more than
> During the early 1880s, David McConnell, the son of Irish immigrants, eked out a livelihood in New York City by selling books door to door. The persistent McConnell tried one gimmick after another to boost his sales. One evening, he prepared a home-made
> Lore Levi was worried as she scanned the most recent monthly bank statement for the Howard Street Jewelers. 1 For decades, she and her husband, Julius, had owned and operated the small business that they had opened after fleeing Nazi Germany during Worl
> In 1890, the Brooklyn Trolley Dodgers professional baseball team joined the National League. Over the following years, the Dodgers would have considerable difficulty competing with the other baseball teams in the New York City area. Those teams, principa
> On the morning of October 14, 2011, Michael Woodford met with the 15-member board of directors of Tokyo-based Olympus Corporation. 1 Woodford, a native of Great Britain who had been appointed Olympus’s chief executive officer (CEO) two weeks earlier, exp
> The surging demand for petroleum products in recent decades has produced a windfall of revenues for many oil-rich Islamic countries in the Middle East, including, among others, Kuwait, Saudi Arabia, and the United Arab Emirates. Because Islam limits the
> In 1956, the Republic of the Sudan obtained its independence from Great Britain. Although unified, Sudan was effectively two countries within one. Northern Sudan, home of the nation’s capital, Khartoum, was controlled by Islamic fundamentalists, while so
> In January 2007, Matthew Neumann and Nicholas Tides, two Boeing employees, transferred to the company’s internal audit department. Neumann, who worked in Boeing’s Seattle headquarters, and Tides, who was based in St. Louis, believed that the move would a
> The Horn of Africa has long played an important role in world history. Most historians believe that the large triangular peninsula that juts into the Indian Ocean along the east coast of Africa was the home of the legendary Kingdom of Punt, an important
> The black Toyota minivan made slow but steady progress down the narrow, unpaved road as it approached the village of Takhli in south central Thailand, approximately 150 miles north of Bangkok. On either side of the bumpy road were fields of sugarcane, de
> In 1996, two friends and business partners, Jia Xiao Gong and Weizhou Lian, founded Longtop Financial Technologies Limited in Beijing. Gong served as Longtop’s chair-man of the board, while Lian assumed the title of chief executive officer (CEO). The two
> “Excuse me, are you Jake Tadlock?” 1 “No, my name is Eli. Eli Arezzo.” “Hello, Eli. My name is Olivia. Olivia Thomas. I’m sorry. I was told that this was Jake’s cubicle.” “No need to be sorry. Jake’s cubicle is around the corner,” Eli replied as he poin
> Frank Coleman pounded away at his calculator as he tried in vain to reconcile his number for the LIFO reserve to the figure recorded by the client. 1 Frustrated and fatigued, Frank glanced at his wristwatch; he couldn’t believe it was 9:40 p.m. Frank im
> In the mid-1990s, KPMG Peat Marwick audited a small, Dallas-based drugstore chain, Texas Drug Warehouse (TDW). Before beginning the company’s 1995 audit, KPMG “made a business decision to reduce the number of hours it would expend on the TDW audit and to
> Ladislas Nay immigrated to the United States from Hungary in 1921 at the age of 18. The opportunities offered by his new land excited the industrious young immigrant and he promised himself that he would make the most of them. Shortly after arriving in t
> In the business world of the Roaring Twenties, the schemes and scams of flimflam artists and confidence men were legendary. The absence of a strong regulatory system at the federal level to police the securities markets—the Securities and Exchange Commis
> Historians disagree when the first email message caromed down the information superhighway, but there is no dispute that email was the Internet’s first “killer app.” Email quickly became the primary communication medium within the business world. By 2015
> In 2012, Reuters, an international news agency based in London, startled the U.S. accounting profession. A Reuters article reported that Washington Council Ernst & Young (WCEY), a registered lobbying firm and division of Ernst & Young (EY), was providing
> Attracting customers and closing sales are challenges that face all retailers, ranging from a Piggly Wiggly grocery in a small southern town to the Giorgio Armani Boutique nestled among the elegant shops lining Rodeo Drive in Beverly Hills. Besides the n
> Sarah Russell grew up in a small town in the flatlands of western Kansas where she was born. 1 In high school, she was homecoming queen, valedictorian of her graduating class, point guard on her basketball team for two years, and a candy striper (volunt
> In the late 1990s, James Fazio reached what many CPAs consider the pinnacle of success in the accounting profession, namely, partnership in one of the Big Four public accounting firms. For more than a decade, Fazio served as an audit partner with Deloitt
> “So, any good news on the staffing front, Till?” Sophie White Eagle asked in between bites of a Christmas cookie. 1 “Nope. Still short at least one staff accountant,” Tillman Rollins replied glumly before adding, “probably two.”Tillman Rollins and his
> Madison Wells should have been happy. 1 Another hectic busy season was coming to an end which meant the audit manager’s standard workload would drop from 55 to 65 hours per week to a much more reasonable 45 hours. But Madison wasn’t thinking of the end
> “No, that’s okay, Bea. I’ll write that memo this weekend and send it to Mr. Fielder. You go on home.” 1 “Are you sure, Chuck? I don’t mind staying a while longer.” “Thanks, Bea, but you’ve already put in too much overtime this week.” After he sent his s
> “Oh no, not Store 51,” Avis Love moaned under her breath. For the third time, Avis compared the dates listed in the cash receipts journal with the corresponding dates on the bank deposit slips. Avis shook her head softly and leaned back in her chair. The
> One month after being promoted to audit senior, Tommy O’Connell was assigned to the audit engagement team for the Altamesa Manufacturing Company. 1 Tommy worked out of his Big Four employer’s Fort Worth practice office, while Altamesa was headquarted in
> After spending much of the previous three months working elbow-to-elbow with as many as six colleagues in a cramped and poorly ventilated conference room, Hamilton Wong was looking forward to moving on to his next assignment. 1 Wong served as an in-charg
> “Bill, will you have that inventory memo done by this afternoon?” 1 “Yeah, Sam, it’s coming along. I should have it done by five, or so.” “Make it three . . . or so. Okay, Bub?” Bill responded with a smile and a nod. He had a good relationship with Sam H
> Leigh Ann Walker graduated from a major state university with a bachelor’s degree in accounting. 1 During her college career, Walker earned a 3.9 grade point average and participated in several extracurricular activities, including three student business
> In 1983, Marta Giordano inherited the restaurant that her grandfather, Alberto Buranello, had established shortly after returning to his hometown of Boston after serving in World War I. 1 For nearly a century, the restaurant, Buranello’s Ristorante, has
> Richard Grimes glanced at his wristwatch as he pulled into the nearly deserted parking lot of the corporate headquarters of McCaleb Medical Corporation (MMC). 1 It was 6:25 a.m. on a cold and overcast Friday morning in February. Based in a suburb on the
> In late 2003, Le-Nature’s Inc., a Pennsylvania-based beverage company, selected BDO Seidman to replace Ernst & Young (EY) as its independent audit firm. A few months earlier, EY had insisted that Le-Nature’s retain an external law firm to investigate all
> No doubt, Guy Enright was apprehensive as he talked to the mysterious stranger on the phone. At the time, Enright, a British citizen and Chartered Accountant, was working on an unusual engagement for his employer, KPMG. 1,2 The Big Four accounting firm h
