AutoMax is an online car retailer that supports its customers with a live call center. The call center operates daily from 8:00 am to 9:00 pm. Call center employees work 9 hour shifts that
may begin at the following five times: 8:00 am, 9:00 am, 10:00 am, 11:00 am, or 12:00 p(noon). Employees get a one-hour break in the middle of their shift. Workers that start at 8:00 or 9:00 are paid $211 for each shift worked. Workers starting at 10:00, 11:00, or noon are paid $232, $242, and $253 per shift, respectively. The following table summarizes the minimum number of workers needed during each hour of daily operations in order to handle the forecasted call volume. The company would like to determine how many workers to schedule for each shift in order to handle the call volume in the most efficient manner
a. Formulate a LP model for this problem.
b. Implement your model in a spreadsheet and solve it.
c. What is the optimal solution?
> Use Solver to create a Sensitivity Report for question 35 at the end of Chapter 3 and answer the following questions. a. Is the solution degenerate? b. Is the solution unique? c. How much should the recycler be willing to pay to acquire more cardboard? d
> CaroliNet is a satellite TV service provider for residential customers in the state of North Carolina. The company is planning to expand and offer satellite TV service in South Carolina as well. The company wants to establish a set of service hubs throug
> Use Solver to create a Sensitivity Report for question 34 at the end of Chapter 3 and answer the following questions: a. Is the solution unique? b. If Sentry wants to increase their production capacity in order to meet more of the demand for their produc
> The Embassy Lodge hotel chain wants to compare its brand efficiency to that of its major competitors using DEA. Embassy collected the following data reported in industry trade publications. Embassy views customers’ perceptions of satisf
> Use Solver to create a Sensitivity Report for question 33 at the end of Chapter 3 and answer the following questions. a. Is the solution degenerate? b. Is the solution unique? c. Use a Solver Plot to determine the maximum price the Pelletier Corporation
> Fidelity Savings & Loans (FS&L) operates a number of banking facilities throughout the Southeastern United States. The officers of FS&L wants to analyze the efficiency of the various branch offices using DEA. The following data has been selec
> Hamilton & Jovanovich (H&J) is a global investment company, providing start-up capital to promising new ventures around the world. Due to the nature of its business, H&J holds funds in a variety of countries and converts between currencies as
> Use Solver to create a Sensitivity Report for question 24 at the end of Chapter 3 and answer the following questions: a. Are there alternate optimal solutions to this problem? Explain. b. What is the highest possible octane rating for regular gasoline, a
> Winter Wear house operates a clothing store specializing in ski apparel. Given the seasonal nature of their business, there is often somewhat of an imbalance between when bills must be paid for inventory purchased and when the goods are actually sold and
> Use Solver to create a Sensitivity Report for question 29 at the end of Chapter 3 and answer the following questions. a. What is the maximum level profit that can be achieved for this problem? b. Are there alternate optimal solutions to this problem? If
> The CFO for Eagle Beach Wear and Gift Shop is in the process of planning for the company’s cash flows for the next six months. The following table summarizes the expected accounts receivables and planned payments for each of these month
> Refer to the previous question. Suppose location 1 has 15 cars available rather than 16. Create a Sensitivity Report for this problem and answer the following questions: a. Is the optimal solution unique? How can you tell? b. According to the Sensitivity
> Companies are often interested in segmenting their customers to better target specific product offerings to meet specific customer needs. The file CustomerData.xlsx that accompanies this book contains data on 198 customers for an online retailer. Specifi
> The accounting firm of Coopers & Andersen is conducting a benchmarking survey to assess the satisfaction level of their clients versus clients served by competing accounting firms. The clients are divided into four groups: A total of 4,000 companies
> Use Solver to create a Sensitivity Report for question 18 at the end of Chapter 3 and answer the following questions: a. Is the optimal solution unique? How can you tell? b. Which location is receiving the fewest cars? c. Suppose a particular car at loc
> A regional quality inspector for Green Roof Inns has 16 properties she must visit next month. The driving time from one property to the next is proportional to the straight-line distance between the properties. The X and Y coordinate for each property ar
> Refer to the previous question. Suppose the investments available to the Merrits have the following levels of risk associated with them. If the Merrits want the weighted average risk level of their investments to not exceed 4, how much money will they
> So how am I going to spend this money,” thought Martha Lentz as he sat staring at the pictures and posters of manatees around his office. An avid environmentalist, Martha is the president of “Friends of the Manatees&ac
> Use Solver to create a Sensitivity Report for question 17 at the end of Chapter 3 and answer the following questions: a. Is the solution degenerate? b. Is the solution unique? c. Explain the signs of the reduced costs for each of the decision variables.
> During the execution of the B&B algorithm, many candidate problems are likely to be generated and awaiting further analysis. In the B&B example in this chapter, we chose the next candidate problem to analyze in a rather arbitrary way. What other, more st
> Francois and Camille Merrit recently inherited a substantial amount of money from a deceased relative. They want to use part of this money to establish an account to pay for their daughter’s college education. Their daughter, Lisa, will
> Use Solver to create a Sensitivity Report for question 16 at the end of Chapter 3 and answer the following questions: a. Is the solution degenerate? b. Is the solution unique? c. Suppose the profit per pallet of Tahoe panels went down by $40. Would the
> Solve the following problem manually using the B&B algorithm. You can use the computer to solve the individual problems generated. Create a branch-and-bound tree to display the steps you complete
> Jack Potts recently won $1,000,000 in Las Vegas and is trying to determine how to invest his winnings. He has narrowed his decision down to five investments, which are summarized in the following table. If Jack invests $1 in investment A at the beginnin
> Use Solver to create a Sensitivity Report for question 15 at the end of Chapter 3 and answer the following questions: a. How much would electric trimmers have to cost in order for the company to consider purchasing these items rather than making them? b.
> Max Gooding is tired of losing money in his office’s weekly football pool and has decided to try to do something about it. Figure 8.44 (and file Football.xlsx that accompanies this book) contains a listing of the teams in the Imaginary
> A natural gas trading company wants to develop an optimal trading plan for the next 10 days. The following table summarizes the estimated prices (per thousand cubic feet [cf]) at which the company can buy and sell natural gas during this time. The compan
> Use Solver to create a Sensitivity Report for question 14 at the end of Chapter 3 and answer the following questions: a. Is the solution degenerate? b. Does the problem have alternate optimal solutions? c. If Sable University wanted 1,000 more maroon shi
> Brue Lee is the Vice President of Purchasing for the consumer electronics division of the Major Electric Corporation (MEC). The company recently introduced a new type of video camcorder that has taken the market by storm. Although Brue is pleased with th
> Alaskan Railroad is an independent, stand-alone railroad operation not connected to any other rail service in North America. As a result, rail shipments between Alaska and the rest of North America must be shipped by truck for thousands of miles or loade
> The Dot Com Corporation is implementing a pension plan for its employees. The company intends to start funding the plan with a deposit of $50,000 on January 1, 2022. It plans to invest an additional $12,000 one year later, and continue making additional
> Use Solver to create a Sensitivity Report for question 13 at the end of Chapter 3 and answer the following questions: a. If the company could get 50 more units of routing capacity, should they do it? If so, how much should they be willing to pay for it?
> Home Sweet Home Appliances manufactures specialty kitchen appliances at its factory in Hoover, Alabama. Presently, the company is preparing to deliver custom refrigerators and dishwashers to distributors in a number of different cities. It has 20 refrige
> Carter Enterprises is involved in the soybean business in South Carolina, Alabama, and Georgia. The president of the company, Earl Carter, goes to a commodity sale once a month where he buys and sells soybeans in bulk. Carter uses a local warehouse for s
> Acme Manufacturing makes a variety of household appliances at a single manufacturing facility. The expected demand for one of these appliances during the next four months is shown in the following table along with the expected production costs and the ex
> A winery has the following capacity to produce an exclusive dinner wine at either of its two ineyards at the indicated costs: Four Italian restaurants around the country are interested in purchasing this wine. Because The wine is exclusive, they all wa
> Paul Bergey is in charge of loading cargo ships for International Cargo Company (ICC) at the port in Newport News, Virginia. Paul is preparing a loading plan for an ICC freighter destined for Ghana. An agricultural commodities dealer wants to transport t
> Amy White is the director of marketing for the Imagination Toy Corporation (ITC). She just received a phone call from her boss indicating that the company’s board of directors gave final approval for the production and marketing of the Mighty Morphin’ Mo
> In the aftermath of the September 11, 2001, terrorist attacks on the World Trade Center, the New York City Department of Design and Construction was put in charge of recovery and clean-up operations at the site. The attack killed 2,823 people, destroyed
> Ba hari Harrison is a financial analyst for Wolverine Manufacturing, a company that produces engine bearings for the automotive industry. Wolverine is in the process of hammering out a new labor agreement with its unionized workforce. One of the major co
> Darren Restaurants owns and operates several different restaurant chains including Red Snapper and the Olive Grove. The company is considering opening a number of new units in Ohio. There are 10 different sites available for the company to build new rest
> Refer to question 20 at the end of Chapter 2. Implement a spreadsheet model for this problem and solve it using Solver. Data from question 20 chapter 2: American Auto is evaluating their marketing plan for the sedans, SUVs, and trucks they produce. A
> Refer to question 17 at the end of Chapter 2. Implement a spreadsheet model for this problem and solve it using Solver. Data from question 17 chapter 2: The Electro tech Corporation manufactures two industrial-sized electrical devices: generators and
> Refer to question 16 at the end of Chapter 2. Implement a spreadsheet model for this problem and solve it using Solver. Data from question 16 chapter 2: The Gourmet Grill Company manufactures and sells two different types of grills: propane and electri
> Cal Hampton is on the board of directors of Crossroad Academy, a private, parent-run, K-12 school located in the town of Shawsville, VA. In an effort to increase enrollment at this school in the coming year, several months ago, Cal and other board member
> Refer to question 14 at the end of Chapter 2. Implement a spreadsheet model for this problem and solve it using Solver. Data from question 14 chapter 2: Oakton Manufacturing makes two types of rocking chairs specifically designed for men and women kno
> Refer to question 13 at the end of Chapter 2. Implement a spreadsheet model for this problem and solve it using Solver Data from question 13 chapter 2: Bobbins Manufacturing produces softball and baseballs for youth recreation leagues. Each softball c
> A variable that assumes an optimal value between its lower and upper bounds has a reduced cost value of zero. Why must this be true? (Hint: What if such a variable’s reduced cost value is not zero? What does this imply about the value of the objective fu
> Ho wie Jones used the following information to calculate the profit coefficients for AquaSpasand Hydro- Luxes: pumps cost $225 each, labor costs $12 per hour, tubing costs $2 per foot. In addition to pumps, labor, and tubing, the production of Aqua-Spas
> A paper recycling company converts newspaper, mixed paper, white office paper, and cardboard into pulp for newsprint, packaging paper, and print stock quality paper. The following table summarizes the yield for each kind of pulp recovered from each ton o
> The Sentry Lock Corporation manufactures a popular commercial security lock at plants in Macon, Louisville, Detroit, and Phoenix. The per unit cost of production at each plant is $35.50, $37.50, $39.00, and $36.25, respectively, while the annual producti
> The Pelletier Corporation has just discovered that it will not have enough warehouse space for the next five months. The additional warehouse space requirements for this period are listed in the following table: To cover its space requirements, the firm
> The Pitts Barbecue Company makes three kinds of barbecue sauce: Extra Hot, Hot, and Mild. Pitts’ vice president of marketing estimates that the company can sell 8,000 cases of its Extra Hot sauce plus 10 extra cases for every dollar it spends promoting t
> Virginia Tech operates its own power generating plant. The electricity generated by this plant supplies power to the university and to local businesses and residences in the Blacksburg area. The plant burns three types of coal, which produce steam that
> Sam Ellis is worried. As president and CEO of Forward Software, Sam introduced a new spreadsheet product, Cinco, to the market last year. Forward Software has been developing and marketing high-quality software packages for more than 5 years, but these p
> Radmore Memorial Hospital has a problem in its fluids analysis lab. The lab has three machines available that analyze various fluid samples. Recently, the demand for analyzing blood samples has increased so much that the lab director is having difficult
> Holiday Fruit Company buys oranges and processes them into gift fruit baskets and fresh juice. The company grades the fruit it buys on a scale from 1 (lowest quality) to 5 (highest quality). The following table summarizes Holiday’s curr
> A manufacturer of prefabricated homes has decided to subcontract four components of the homes. Several companies are interested in receiving this business, but none can handle more than one subcontract. The bids made by the companies for the various subc
> The Shop at Home Network sells various household goods during live television broadcasts. The company owns several warehouses to hold many of the goods it sells but also leases extra warehouse space when needed. During the next five months the company ex
> A company is trying to determine how to allocate its $145,000 advertising budget for a new product. The company is considering newspaper ads and television commercials as its primary means for advertising. The following table summarizes the costs of adve
> The Molokai Nut Company (MNC) makes four different products from macadamia nuts grown in the Hawaiian Islands: chocolate-coated whole nuts (Whole), chocolate-coated nut clusters (Cluster), chocolate-coated nut crunch bars (Crunch), and plain roasted nuts
> Riverside Oil Company in eastern Kentucky produces regular and supreme gasoline. Each barrel of regular sells for $21 and must have an octane rating of at least 90. Each barrel of supreme sells for $25 and must have an octane rating of at least 97. Each
> A trust officer at the Blacksburg National Bank needs to determine how to invest $100,000 in the following collection of bonds to maximize the annual return. The officer wants to invest at least 50% of the money in short-term issues and no more than 50
> Valu-Com Electronics manufactures five different models of telecommunications interface Cards for PCs and laptops. As summarized in the following table, each of these devices requires differing amounts of printed circuit board, resistors, memory chips, a
> Aire-Co produces home dehumidifiers at two different plants in Atlanta and Phoenix. The per unit cost of production in Atlanta and Phoenix is $400 and $360, respectively. Each plant can produce a maximum of 300 units per month. Inventory holding costs ar
> In the mid-1990s, DHL was the world’s largest shipping company, with $5.7 billion in revenue and 60,000 employees. Larry Hillbloom was the “H” in DHL and founder of the company. DHL started on a shoestring budget in 1969 with a business plan to deliver s
> Create a Sensitivity Report for Electro-Poly’s make vs. buy problem in section 3-9 of Chapter 3 and answer the following questions. a. Is the solution degenerate? b. How much can the cost of making model 1 slip rings increase before it becomes more econo
> Use Solver to create Answer and Sensitivity Reports for question 26 at the end of Chapter 2 and answer the following questions: a. If the profit on doors increased to $700 would the optimal solution change? b. If the profit on windows decreased to $200 w
> The Rent-A-Dent car rental company allows its customers to pick up a rental car at one location and return it to any of its locations. Currently, two locations (1 and 2) have 16 and 18 surplus cars, respectively, and four locations (3, 4, 5, and 6) each
> The Weed wacker Company manufactures two types of lawn trimmers: an electric model and a gas model. The company has contracted to supply a national discount retail chain with a total of 30,000 electric trimmers and 15,000 gas trimmers. However, Weed mwac
> Bear land Manufacturing produces 4 different types of wood paneling. Each type of paneling is made by gluing and pressing together a different mixture of pine and oak chips. The following table summarizes the required amount of gluing, pressing, and mix
> Krouscas Foods makes a special blend of oil that is popular in Greek cooking. They import oil from two vendors and blend it to ensure that the resulting product contains at least 40% olive oil, 20% sunflower oil, and at least 30% corn oil. Vendor 1 can p
> Game Day Fashions makes custom t-shirts for fans of college university sports teams. Currently, the company is trying to determine the best way to fill an order it received from Sable University. The official colors of Sable University are orange and ma
> This chapter introduces the quote “All models are wrong, but some are useful.” from George Box. Describe a real-world situation where a model was wrong but useful.
> Refer to question 27 at the end of Chapter 2. Implement a spreadsheet model for this problem and solve it using Solver. Data from question 27 chapter 2: PC-Express is a computer retail store that sells desktops and laptops. The company earns $600 on e
> Refer to question 26 at the end of Chapter 2. Implement a spreadsheet model for this problem and solve it using Solver Data from question 26 chapter 2: Sanderson Manufacturing produces ornate, decorative wood frame doors and windows. Each item produce
> In a summer plagued by drought and heat, many Southern crops are withering in the fields, taking farmers’ profits down with them. Some farmers are fighting to break even. But others have had to give up hope that this year’s crop will survive to harvest.
> Refer to question 25 at the end of Chapter 2. Implement a spreadsheet model for this problem and solve it using Solver. Data from question 25 chapter 2: A farmer in Georgia has a 100-acre farm on which to plant watermelons and cantaloupes. Every acre
> Refer to question 24 at the end of Chapter 2. Implement a spreadsheet model for this problem and solve it using Solver. Data from question 24 chapter 2: The Quality Desk Company makes two types of computer desks from laminated particle board. The Pre
> Refer to question 23 at the end of Chapter 2. Implement a spreadsheet model for this problem and solve it using Solver Data from question 23 chapter 2: Zippy motorcycle manufacturing produces two popular pocket bikes (miniature motorcycles with 49cc en
> The following data summarizes the per-day cost of crashing the activities in the problem described in the previous question. a. Create an LP model to determine the least costly way of crashing the project to complete it within 20 days. b. By how much sh
> Consider the following set of activities: a. Draw the CPM network for this problem. b. Create a spreadsheet to calculate and summarize the earliest and latest start and finish times, the slack for each activity, and the critical activities. c. What is t
> Consider the following set of activities: a. Draw the CPM network for this problem. b. Identify each path through the network and its expected length. c. What is the critical path?
> Consider the following set of activities: a. Draw the CPM network for this problem. (Remember that a CPM network requires unique start and finish nodes.) b. Manually determine the earliest and latest start and finish times for each activity and the amou
> Consider the following set of activities: a. Draw the CPM network for this problem. b. Manually determine the earliest and latest start and finish times for each activity and the amount of slack for each activity. c. What is the critical path? d. How lo
> Consider the CPM network for the following set of activities: Is it necessary to draw an arc from the node for activity A to the node for activity C? Why or why not?
> In illustrating how to simulate an activity network, we used a triangular distribution based on three time estimates to generate random activity times. What problem might be encountered if we assume that activity times were normally distributed? (Hint: C
> Anyone who has suffered with an acute or chronic illness is probably very appreciative for whatever drugs are available to cure or manage the disease. In the United States, the Food and Drug Administration (FDA) is the governmental agency that oversees t
> Refer to the previous problem. Suppose that the maximum time listed for each activity is actually its normal completion time. Further assume that the maximum number of crash days per activity and cost per crash day are as follows: a. Create and solve an
> A cosmetics company has identified a set of activities that must be performed in order to bring a new product to market. The activities, their precedence relations, and time estimates to complete each activity (in days) are shown in the following table.
> The activities summarized in the following table must be performed by the promoter of a country music concert in Dallas. a. Draw the activity network for this problem. b. According to PERT, what is the expected length of time required to accomplish thes
> Refer to the previous question. Create a spreadsheet model to simulate the completion times for the auditing project. Assume that activity times follow a triangular distribution and perform 500 replications on the model. a. Estimate the probability of ea
> A partner in the national accounting firm mentioned in the previous questions does not believe the time estimates for each activity can be specified with certainty. Instead, she prefers to specify a minimum, most likely, and maximum time estimate for eac
> Refer to the previous question. Suppose that each of the audit activities can be crashed by the amounts indicated in the following table. a. What is the earliest the audit could be completed and what is the incremental cost associated with this schedule
> A national accounting firm has identified the following set of activities that must occur to carry out an audit for one of their major clients a. Draw the CPM network for this problem. b. Create a spreadsheet to calculate and summarize the earliest and
> Throughout this chapter, we assumed that a project manager identifies and organizes the activities in a project, estimates the time required for each activity, then determines how quickly the project can be completed. However, the deadlines for some proj
> Refer to the previous question. Create a spreadsheet model to simulate the completion times for Koene’s move. Assume that activity times follow a triangular distribution and perform 500 replications on the model. a. Estimate the probab
> Refer to the previous question. Suppose a partner in Koene Technology does not believe the time estimates for each activity can be specified with certainty. Instead, he prefers to specify a minimum, most likely, and maximum number of days for each activi
> I hope this goes better than last time,” thought Craig Rooney as he thought about having to walk into the city council’s chambers next week. Craig is the assistant chief of police in Newport, VA and, each September, he has to provide the city council wit
> Koene Technology is a rapidly growing nanotechnology firm. The company is moving into a new building that will allow it more research lab space and improved computing facilities. The lease on the new facility has already been signed and architectural ren