After the rst exam in a statistics course, Professor Katula surveyed 14 randomly selected students to determine the relation between the amount of time they spent studying for the exam and exam...

Lisun Company produces a variety of gardening tools and aids. The company is examining the possibility of investing in a new production system that will reduce the costs of the current system. The...

Compound A diffuses through a 4-cm-long tube and reacts as it diffuses. The equation governing diffusion with reaction is Dd 2 A / dx 2 kA = 0 At one end of the tube, there is a large source of A at...

A package of light bulbs promises an average life of more than 750 hours per bulb. A consumer group did not believe the claim and tested a sample of 40 bulbs. The average lifetime of these 40 bulbs...

The manager of a fleet of automobiles is testing two brands of radial tires and assigns one tire of each brand at random to the two rear wheels of eight cars and runs the cars until the tires wear...

In exercise 7 a sales manager collected the following data on x = annual sales and y 5 years of experience. The estimated regression equation for these data is y = 80 + 4x. a. Compute SST, SSR, and...

The amounts (in billions of dollars) the U.S. federal government spent on research and development for defense from 2010 through 2014 can be approximated by the model y = 0.5079t2 8.168t + 95.08...

The National Underwriter Company in Cincinnati, Ohio, publishes property and casualty insurance data. Given here is a portion of the data published. These data include information from the U.S....

The probability that a corporation makes charitable contributions is .72. Two corporations are selected at random, and it is noted whether or not they make charitable contributions. a. Draw a tree...

A cylindrical hole is drilled in a block, and a cylindrical piston is placed in the hole. The clearance is equal to one-half the difference between the diameters of the hole and the piston. The...

Assume that the following quantity discount schedule is appropriate. If annual demand is 120 units, ordering costs are $20 per order, and the annual holding cost rate is 25%, what order quantity...

The following profit payoff table was presented in Problem 1. Suppose that the decision maker obtained the probability assessments P(s1) = 0.65, P(s2) = 0.15, and P(s3) = 0.20. Use the expected value...

ParFore created a website to market golf equipment and golf apparel. Management would like a special pop-up offer to appear for female website visitors and a different special pop-up offer to appear...

According to Nielsen Media Research, approximately 52% of all U.S. households have digital cable television. In addition, 84% of all U.S. households have multiple TV sets. Suppose 45% of all U.S....

Use MacKinnon, White, and Davidsons PE test to determine whether a linear or loglinear production model is more appropriate for the data in Appendix Table F6.1. (The test is described in Section...

A study was made on the amount of converted sugar in a certain process at various temperatures. The data were coded and recorded as follows:(a) Estimate the linear regression line.(b) Estimate the...

Cranberries can be harvested using either a wet method or a dry method. Dry-harvested cranberries can be sold at a premium, while wet-harvested cranberries are used mainly for cranberry juice and...

A textbook publisher wants to determine what percentage of college professors either require or recommend that their students purchase textbook packages with supplemental materials, such as study...

Given a standardized normal distribution (with a mean of 0 and a standard deviation of 1, as in Table E.2), what is the probability that a. Z is between 1.57 and 1.84? b. Z is less than 1.57 or...

In 2008, the Centers for Disease Control and Prevention reported that 34% of adults in the United States are obese. A county health service planning a new awareness campaign polls a random sample of...

Researchers investigated how the size of a bowl affects how much ice cream people tend to scoop when serving themselves. At an "ice cream social," people were randomly given either a 17 oz or a 34 oz...

Refer to the Century National Bank data. Is it reasonable that the distribution of checking account balances approximates a normal probability distribution? Determine the mean and the standard...

Shoe Shine is a local retail shoe store located on the north side of Centerville. Annual demand for a popular sandal is 500 pairs, and John Dirk, the owner of Shoe Shine, has been in the habit of...

McGivern Jewelers is located in the Levis Square Mall just south of Toledo, Ohio. Recently it ran an advertisement in the local newspaper reporting the shape, size, price, and cut grade for 33 of its...

You work for a large global management consulting company. Of the entire work force of analysts, 55% have had no experience in the telecommunications industry, 32% have had limited experience (less...

Table P-18 contains data values that represent the monthly sales (in billions of dollars) of all retail stores in the United States. Using the data through 1994, perform a decomposition analysis of...

The reorder point is defined as the lead-time demand for an item. In cases of long lead times, the lead-time demand and thus the reorder point may exceed the economic order quantity Q*. In such...

An important feature of tablets is battery life, the number of hours before the battery needs to be recharged. The file Tablets contains the battery life of 12 WiFi only and 7 3G/4G/ WiFi 9 through...

A scrap metal dealer claims that the mean of his cash sales is no more than $80, but an Internal Revenue Service agent believes the dealer is untruthful. Observing a sample of 20 cash customers, the...

Alan Resnik, a friend of Ray Cahnman, bet Ray $5 that Ray's car would not start five days from now (see Problem 15-8). (a) What is the probability that it will not start five days from now if it...

Prepare a managerial report that addresses the following issues and recommends an order quantity for the Weather Teddy product. 1. Use the sales forecasters prediction to describe a normal...

Tattooed Democrats Find the sample size needed to estimate the percentage of Democrats who have tattoos. Use a 0.05 margin of error, use a confidence level of 99%, and use results from a prior Harris...

A company selling glass ornaments by mail-order expects, from previous history, that 6% of the ornaments it ships will break in shipping. You purchase two ornaments as gifts and have them shipped...

The average annual total return for U.S. Diversified Equity mutual funds from 1999 to 2003 was 4.1% (BusinessWeek, January 26, 2004). A researcher would like to conduct a hypothesis test to see...

Consider the following probabilities: P (Ac) = 0.30, P (B) = 0.60, and P (A Bc) = 0.24. Find: a. P (A | Bc) b. P (Bc | A) c. Are A and B independent events? Explain.

A 20102011 poll conducted by Gallup, (www.gallup.com/poll/148994/Emotional-Health Higher- Among-Older-Americans.aspx) examined the emotional health of a large number of Americans. Among other things,...

A survey found that in a sample of 75 families, 26 owned dogs. A survey done 15 years ago found that in a sample of 60 families, 26 owned dogs. At = 0.05 has the proportion of dog owners changed...

Reconsider the data presented in Exercise 6.21. (a) Rework both parts (a) and (b) of Exercise 6.21 using the x and s charts. (b) Does the s chart detect the shift in process variability more quickly...

A survey sponsored by the Vision Council showed that 79% of adults need correction (eyeglasses, contacts, surgery, etc.) for their eyesight. If 20 adults are randomly selected, find the probability...

Refer to the following chart: a. What is the name given to this type of chart? b. Suppose that 1,000 graduates will start a new job shortly after graduation. Estimate the number of graduates whose...

It costs $25 to bet on a horse race. The horse has a 1/8 chance of winning and a 1/4 chance of placing 2nd or 3rd. You win $125 if the horse wins and receive your money back if the horse places 2nd...

Ten young adults living in California rated the taste of a newly developed sushi pizza topped with tuna, rice, and kelp on a scale of 1 to 50, with 1 indicating they did not like the taste and 50...

Use the given graph of f to state the value of each quantity, if it exists. If it does not exist, explain why. (a) limx→1- f(x) (b) limx→1+ f(x) (c) limx→1 f(x) (d) limx→5 f(x)...

A dam is inclined at an angle of 30 from the vertical and has the shape of an isosceles trapezoid 100 ft wide at the top and 50 ft wide at the bottom and with a slant height of 70 ft, find the...

The Two-Rivers Oil Company near Pittsburgh transports gasoline to its distributors by truck. The company recently contracted to supply gasoline distributors in southern Ohio, and it has $600,000...

Linda Stanyon has been the production manager for Plano Produce for over eight years. Plano Produce is a small company located near Plano, Illinois. One produce item, tomatoes, is sold in cases, with...

Young Professional magazine was developed for a target audience of recent college graduates who are in their first 10 years in a business/professional career. In its two years of publication, the...

Seventy new jobs are opening up at an automobile manufacturing plant, but 1000 applicants show up for the 70 positions. To select the best 70 from among the applicants, the company gives a test that...

For the 300 trading days from January 11, 2012 to March 22, 2013, the daily closing price of IBM stock (in $) is well modeled by a Normal model with mean $197.92 and standard deviation $7.16....

Galaxy Cloud Services operates several data centers across the United States containing servers that store and process the data on the Internet. Suppose that Galaxy Cloud Services currently has five...

Among 150 IRS employees in a large city, only 30 are women. If 10 of the applicants are chosen at random to provide free: fax assistance for the residents of this city, use the binomial approximation...

The file P02_07.xlsx includes data on 204 employees at the (fictional) company Beta Technologies. For this problem, consider this data set as the population frame. a. Using the method in this section...

In your own words, explain the difference between beyond all reasonable doubt and beyond all doubt. Use these phrases to explain why we never accept the statement in the null hypothesis.

In a study by P. M. West titled "The Lion's Mane" (American Scientist, Vol. 93, No. 3, pp. 226-236), the effects of the mane of a male lion as a signal of quality to mates and rivals was explored....

Maurices Pump Manufacturing Company currently maintains plants in Atlanta and Tulsa that supply major distribution centers in Los Angeles and New York. Because of an expanding demand, Maurice has...

Over the past decade, the mean number of hacking attacks experienced by members of the Information Systems Security Association is 510 per year with a standard deviation of 14.28 attacks. The number...

Suppose 40% of recent college graduates plan on pursuing a graduate degree. Fifteen recent college graduates are randomly selected. a. What is the probability that no more than four of the college...

A recent poll asked 16- to 21-year-olds whether or not they are likely to serve in the U.S. military. The following table, cross-classified by gender and race, reports the percentage of those polled...

Lobsters vary in sizes. The bigger the size, the more valuable the lobster per pound (a 6-pound lobster is more valuable than two 3-pound ones). Lobster merchants will sell entire boatloads for a...

To assess the effectiveness of a cola video ad, a random sample of 38 individuals from a target audience was selected to participate in a copy test. Participants viewed two ads, one of which was the...

The weekly demand for a product is believed to be normally distributed. Use a goodness of fit test and the following data to test this assumption. Use = .10. The sample mean is 24.5 and the sample...

A statistics instructor randomly selected four bags of oranges; each bag labeled 10 pounds, and weighed the bags. They weighed 10.2, 10.5, 10.3, and 10.3 pounds. Assume that the distribution of...

Referring to the contingency table in Problem 4.8, if an employed adult is selected at random, what is the probability that a. The employed adult felt tense or stressed out at work? b. The employed...

Recent research suggests that the amount of time that parents spend talking about numbers can have a big effect on the mathematical development of their children (Levine, Suriyakham, Rowe,...

The waiting time for treatment in a minute-clinic located in a drugstore is monitored using control charts for individuals and the moving range. Table 6E.24 contains 30 successive measurements on...

A quarterback threw 1 interception in his first game, 2 interceptions in his second game, 5 interceptions in his third game, and then he retired. Consider the values of 1, 2, and 5 to be a...

Each of the possible five outcomes of a random experiment is equally likely. The sample space is {a, b, c, d, e}. Let A denote the event {a, b}, and let B denote the event {c, d, e}. Determine the...

Consider the following time series data Using the nave method (most recent value) as the forecast for the next week, compute the following measures of forecast accuracy: a. Mean absolute error b....

AOL Time Warner Inc.'s CNN has been the longtime ratings leader of cable television news. Nielsen Media Research indicated that the mean CNN viewing audience was 600,000 viewers per day during 2002...

Suppose the annual employer 401(k) cost per participant is normally distributed with a standard deviation of $625, but the mean is unknown. a. If 73.89% of such costs are greater than $1,700, what is...

Market Researchers, Inc., has been hired to perform a study to determine if the market for a new product will be good or poor. In similar studies performed in the past, whenever the market actually...

Juhn and Sons Wholesale Fruit Distributors employ one worker whose job is to load fruit on outgoing company trucks. Trucks arrive at the loading gate at an average of 24 per day, or 3 per hour,...

For the Billys Bank situation in Problems, the salary and benefits for a teller would be $12 per hour. The bank is open 8 hours each day. It has been estimated that the waiting time cost per hour is...

An economist reports that 560 out of a sample of 1,200 middle-income American households actively participate in the stock market. a. Construct the 90% confidence interval for the proportion of...

A committee in charge of promoting a Ladies Professional Golf Association tournament is trying to determine how best to advertise the event during the two weeks prior to the tournament. The committee...

It appears that the imports of carbon black have been increasing by about 10% annually. a. Determine the logarithmic trend equation. b. By what percent did imports increase, on the average, during...

The H2 Hummer limousine has eight tires on it. A fleet of 1300 H2 limos was fit with a batch of tires that mistakenly passed quality testing. The following table lists the frequency distribution of...

According to the California Educational Code (www.cde.ca.gov/ (www.cde.ca.gov/ls/fa/sf/peguidemidhi.asp), ls/fa/sf/peguidemidhi.asp), students in grades 7 12 should receive 400 minutes of physical...

Let X1, X2, . . . , Xn be a random sample of size n from a geometric distribution for which p is the probability of success. (a) Use the method of moments to find a point estimate for p. (b) Explain...

The following table shows the total revenue (in billions of $) for Walmart Stores, Inc. and Target Corp. for the years 2008-2010. Year...........2008..........2009..........2010...

Lila Battle has determined that the annual demand for number 6 screws is 100,000 screws. Lila, who works in her brother's hardware store, is in charge of purchasing. She estimates that it costs $10...

Endowment income is a critical part of the annual budgets at colleges and universities. A study by the National Association of College and University Business Officers reported that the 435 colleges...

In Problem 12.7 on page 424, you used the plate gap on the bag sealing equipment to predict the tear rating of a bag of coffee. The data are stored in Starbucks. a. Construct a 95% confidence...

The relationship between x = total number of salmon in a creek and y = percentage of salmon killed by bears that were transported away from the stream prior to the bear eating the salmon was examined...

An investor is considering three different television news stocks to complement his portfolio: British Broadcasting Company (BBC), Canadian Broad-casting Company (CBC), and Australian Broadcasting...

One of the theories regarding initial public offering (IPO) pricing is that the initial return y (change from offer to open price) on an IPO depends on the price revision x (change from pre-offer to...

U.S. companies lose $63.2 billion per year from workers with insomnia. Workers lose an average of 7.8 days of productivity per year due to lack of sleep (Wall Street Journal, January 23, 2013). The...

U.S. Customs and Border Protection have been testing automated kiosks that may be able to detect lies. One measurement used (among several) is involuntary eye movements. Using this method alone,...

Referring to Exercise 7, The article "Some Field Experience in the Use of an Accelerated Method in Estimating 28-Day Strength of Concrete" (J. of Amer. Concrete Institute, 1969: 895) considered...

The grades on the midterm examination given in a large managerial statistics class are normally distributed with mean 75 and standard deviation 9. The instructor of this class wants to assign an A...

In a given city, 4 percent of all licensed drivers will be involved in at least one car accident in any given year. Use the Poisson approximation to the binomial distribution to determine the...

The owner of an automobile repair shop studied the waiting times for customers who arrive at the shop for an oil change. The following data with waiting times in minutes were collected over a 1-month...

The table gives enrollments at North Shore High School. a. Find the equation of the regression line. Round the slope and y-intercept to the nearest hundredth. b. What is the slope of the linear...

Let X denote the vibratory stress (psi) on a wind turbine blade at a particular wind speed in a wind tunnel. The article "Blade Fatigue Life Assessment with Application to VAWTS" (J. of Solar Energy...

The Webster Manufacturing Company produces a popular type of serving cart. This product, the SL72, is made from the following parts: 1 unit of Part A, 1 unit of Part B, and 1 unit of Subassembly C....

You plan to develop a new software system that you believe will surpass the success of Google and Facebook combined. In planning for the operating system that you will use, you need to estimate the...

A market researcher at a major clothing company that has traditionally relied on catalog mail-order sales decides to investigate whether the amount of monthly online sales has changed. She compares...

A steel pipe is being carried down a hallway 9 ft wide. At the end of the hall there is a right-angled turn into a narrower hallway 6 ft wide. What is the length of the longest pipe that can be...

Annual per capita consumption of milk is 21.6 gallons (Statistical Abstract of the United States: 2006). Being from the Midwest, you believe milk consumption is higher there and wish to support your...

A survey of 158 introductory statistics students showed the following contingency table. Find each event probability. a. P(V) b. P(A) c. P(A V ) d. P(A V ) e. P(A | V ) f. P(V | A) Cell Phone...