The following data give the weekly amounts spent on groceries for a sample of 45 households. a. How many classes would you recommend? b. What class interval would you suggest? c. What would you...

The following are four observations collected from each of three treatments. Test the hypothesis that the treatment means are equal. Use the .05 significance level. a. State the null and the...

The safety director of a large steel mill took samples at random from company records of minor work-related accidents and classified them according to the time the accident took place. Using the...

The owner of the Original Italian Pizza restaurant chain wants to understand which variable most strongly influences the sales of his specialty deep-dish pizza. He has gathered data on the monthly...

In a survey of 3029 adult Americans, the Harris Poll asked people whether they smoked cigarettes and whether they always wear a seat belt in a car. The table shows the results of the survey. For each...

In each of the following situations, summarize negative aspects of the sample design. a. A newspaper asks readers to vote at its Internet site to determine if they believe government expenditures...

Suppose that P (A|B) = 0.7, P (A) = 0.5, and P (B) = 0.2. Determine P (B|A).

According to an estimate, the average price of homes in Marthas Vineyard, Massachusetts, was $650,000 in 2011 (USA TODAY, August 11, 2011). A recent random sample of 70 homes from Marthas Vineyard...

Estimate the common logarithm of 10 using-linear interpolation. (a) Interpolate between log 8 = 0.903900 and log 12 = 1.0791812. (b) Interpolate between log 9 = 0.9542425 and log 11 = 1.0413927. For...

A quality control specialist has sampled 25 widgets from the production line. A widget can have minor or major defects. Of the 25 sampled widgets, 4 have minor defects and 2 have major defects. What...

Assume that Google, Inc. hires employees on the different business days of the week (Monday through Friday) with equal likelihood. a.If two different employees are randomly selected, what is the...

Nationwide 13.7% of employed wage and salary workers are union members (down from 20.1% in 1983). A random sample of 300 local wage and salary workers showed that 50 belonged to a union. At = 0.05,...

Aurora Radiological Services is a health care clinic that provides radiological imaging services (such as MRIs, X-rays, and CAT scans) to patients. It is part of Front Range Medical Systems that...

Mantel produces a toy carriage, whose final assembly must include four wheels and two seats. The factory producing the parts operates three shifts a day. The following table provides the amounts...

Sascha owns stock in Lewis Corp and she bought a $1,000 corporate bond. The bond pays 6.34% annual interest. a. How much will Sascha receive in annual interest? b. How much will Sascha receive in...

Using data from 2006 and with projections to 2021, total annual expenditures for national health care (in billions of dollars) can be described by E = 7.94x2 + 33.2x + 2190 where x is the number of...

Ten individuals have participated in a diet-modification program to stimulate weight loss. Their weight both before and after participation in the program is shown in the following list is there...

A random sample of 25 bottles of buffered aspirin contain, on average, 325.05 mg of aspirin with a standard deviation of 0.5 mg. Find the 95% tolerance limits that will contain 90% of the aspirin...

Lun Ho Stadium sells 2,200 tickets for a concert. It sells a quarter of them at a 20% discount and a further 10% at a 40% discount. How much must it charge for tickets if it wants to generate an...

Automobile magazines often compare models and rate them in various ways. One question that is often asked of car owners, would you buy the same model again? Suppose that a researcher for one magazine...

It is important for airlines to follow the published scheduled departure times of flights. Suppose that one airline that recently sampled the records of 246 flights originating in Orlando found that...

Every now and then even a good diamond cutter has a problem and the diamond breaks. For one cutter, the rate of breaks is 0.1%. (a) What probability model seems well suited to this problem? Why? (b)...

How much time do Americans living in or near cities spend waiting in traffic, and how much does waiting in traffic cost them per year? The data in the file Congestion include this cost for 31 cities....

The following data show the brand, price ($), and the overall score for six stereo headphones that were tested by Consumer Reports (Consumer Reports website, March 5, 2012). The overall score is...

The shelf life, in days, for bottles of a certain prescribed medicine is a random variable having the density function Find the probability that a bottle of this medicine will have a shell life of(a)...

In Problem 5, if P(s1) = 0.25, P(s2) = 0.50, and P(s3) = 0.25, find a recommended decision for each of the three decision makers. (For the same decision problem, different utilities can lead to...

The file P08_18.xlsx categorizes 250 randomly selected consumers on the basis of their gender, their age, and their preference for our brand or a competitors brand of a low-calorie soft drink. Use a...

In December 2001, 38% of adults with children under the age of 18 reported that their family ate dinner together 7 nights a week. In a recent poll, 403 of 1122 adults with children under the age of...

Use the sample statistics from Exercise 29 and assume the number of vehicles in the sample is 75. (a) Estimate the number of vehicles whose speeds are between 63 miles per hour and 71 miles per hour....

The file FISH.RAW contains 97 daily price and quantity observations on fish prices at the Fulton Fish Market in New York City. Use the variable log(avgprc) as the dependent variable. (i) Regress...

A paper in the Journal of the Association of Asphalt Paving Technologists (Vol. 59, 1990) describes an experiment to determine the effect of air voids on percentage retained strength of asphalt. For...

The Jessie Cohen Clothing Group owns factories in three towns (W, Y and Z) which distribute to three Cohen retail dress shops (in A, B, and C). Factory availabilities, projected store demands, and...

A Monster.com poll of 3057 individuals asked: Whats the longest vacation you plan to take this summer? The following relative frequency distribution summarizes the results. ResponseRelative Frequency...

A U.S. Navy recruiting center knows from past experience that the heights of its recruits have traditionally been normally distributed with mean 69 inches. The recruiting center wants to test the...

The following contingency table shows opinion about global warming among U.S. adults, broken down by political party affiliation (based on a poll in October 2012 by Pew Research found at...

A fast-food chain randomly attaches coupons for prizes to the packages used to serve french fries. Most of the coupons say Play again, but a few are winners. Seventy-five percent of the coupons pay...

A manufacturer of pens has hired an advertising agency to develop an advertising campaign for the upcoming holiday season. To prepare for this project, the research director decides to initiate a...

Baseballs vary somewhat in their rebounding coefficient. A baseball that has a large rebound coefficient will travel farther when the same force is applied to it than a ball with a smaller...

Roedel Electronics produces tablet computer accessories, including integrated keyboard tablet stands that connect a keyboard to a tablet device and holds the device at a preferred angle for easy...

Determine the value of c that makes the function f(x, y) =cxy a joint probability density function over the range 0

Temperatures are measured at various points on a heated plate (Table P20.56). Estimate the temperature at (a) x = 4, y = 3.2, and (b) x = 4.3, y =2.7. x- 2 70.00 48. 15 35.03 27.07 25.00 60.00 90.00...

Refer to the Baseball 2012 data, which report information on the 30 Major League Baseball teams for the 2012 season. a. The mean attendance per team for the season was 2.495 million, with a standard...

The following data represent the number of different communication activities (e.g., cell phone, text messaging, e-mail, Internet, and so on) used by a random sample of teenagers over the past 24...

Listed below are the gross amounts (in millions of dollars) earned from box office receipts for the movie Harry Potter and the Half-Blood Prince. The movie opened on a Wednesday, and the amounts are...

The Davis family of Atlanta, Georgia, is planning its annual summer vacation. Three vacation locations along with criteria weights and location ratings follow. What is the recommended...

For a random sample of 125 British entrepreneurs, the mean number of job changes was 1.91 and the sample standard deviation was 1.32. For an independent random sample of 86 British corporate...

Refer to Problem 5.22. How many cookies in a batch of 100 should the manager expect to discard if company policy requires that all chocolate- chip cookies sold have at least four chocolate-chip...

Consumer Reports provided extensive testing and ratings for 24 treadmills. An overall score, based primarily on ease of use, ergonomics, exercise range, and quality, was developed for each treadmill...

Kruuk et al. (1989) used a stratified sample to estimate the number of otter (Lutra lutra) dens along the 1400-km coastline of Shetland, UK. The coastline was divided into 242 (237 that were not...

The sugar content of the syrup in canned peaches is normally distributed. A random sample of n = 10 cans yields a sample standard deviation of s = 4.8 milligrams. Find a 95% two-sided confidence...

A random sample of n = 9 structural elements is tested for compressive strength. We know that the true mean compressive strength = 5500 psi and the standard deviation is = 100 psi. Find the...

A manufacturer of semiconductor devices takes a random sample of size n of chips and tests them, classifying each chip as defective or non-defective. Let Xi = 0 if the chip is non-defective and Xi =...

A manufacturing company uses an acceptance scheme on production items before they are shipped. The plan is a two-stage one. Boxes of 25 are readied for shipment and a sample of 3 is tested for...

Ms. Lisa Monnin is the budget director for Nexus Media Inc. She would like to compare the daily travel expenses for the sales staff and the audit staff. She collected the following sample...

A study conducted by the Pew Research Center showed that 75% of 18to 34-year-olds living with their parents say they contribute to household expenses (The Wall Street Journal, October 22, 2012)....

Suppose that in Problem 9.16, the standard deviation is 0.012 gallon. a. Repeat (a) through (d) of Problem 9.16, assuming a standard deviation of 0.012 gallon. Data From Problem 9.16: A bottled water...

In a survey of 4013 U.S. adults, 722 say they have seen a ghost. Construct a 99% confidence interval for the population proportion. Interpret the results. If convenient, use technology to construct...

Heller Manufacturing has two production facilities that manufacture baseball gloves. Production costs at the two facilities differ because of varying labor rates, local property taxes, type of...

Refer to the Buena School District bus data. Select the variable referring to the number of miles traveled last month, and then organize these data into a frequency distribution. a. What is a typical...

Consider the following returns for two investments, A and B, over the past four years: a. Which investment provides the higher return? b. Which investment provides less risk? c. Given a risk-free...

A new-car dealer is leasing various brand-new models for the monthly rates (in dollars) listed below. Estimate the true population variance (and standard deviation) in leasing rates with 90%...

Before installing a high-tech laser exhibit near the exit area, a museum of American technology found the average contribution by patrons was $2.75 per person. For a sample of 30 patrons following...

A study was conducted to compare the effect of four manganese rates ( from MnSO4) and four copper rates ( from CuSO4 5H2O) on the yield of soybeans. A large field was subdivided into 32 separate...

Assume that you are working with the results from Problems 11.29 and 11.30. a. What is the value of the test statistic for the interaction effect? b. What is the value of the test statistic for the...

Use CRIME4.RAW for this exercise. (i) Reestimate the unobserved effects model for crime in Example 13.9 but use fixed effects rather than differencing. Are there any notable sign or magnitude changes...

The time between arrivals of customers at an automatic teller machine is an exponential random variable with a mean of 5 minutes. (a) What is the probability that more than three customers arrive in...

Researchers wanted to explore self-esteem in adolescent boys and adolescent girls. They used a 5-point Likert-type self-esteem inventory; a 1 = strongly disagree and 5 = strongly agree. Their results...

Sharp Outfits is trying to decide whether to ship some customer orders now via UPS or wait until after the threat of another UPS strike is over. If Sharp Outfits decides to ship the requested...

Count the number of cars that pass by an intersection during consecutive five-minute periods on a highway leading into a city. Would these data allow us to use the Law of Large Numbers eventually to...

Suppose that a product is shipped in lots of size N = 5,000. The receiving inspection procedure used is single sampling with n = 50 and c = 1. (a) Draw the type-A OC curve for the plan. (b) Draw the...

Solve the following LP problem by using the graphical procedure and by using Excel: Maximize profit = 4X + 5y Subject to the constraints 5X + 2y < 40 3X + 6y < 30 X <7 2X y > 3 x,y >0

Impurities in the batch of final product of a chemical process often reflect a serious problem. From considerable plant data gathered, it is known that the proportion Y of impurities in a batch has a...

A candy company fills a 20-ounce package of Halloween candy with individually wrapped pieces of candy. The number of pieces of candy per package varies because the package is sold by weight. The...

Hits to a high-volume Web site are assumed to follow Poisson distribution with a mean of 10,000 per day. Approximate each of the following: (a) The probability of more than 20,000 hits in a day (b)...

A missile leaves the ground with an initial velocity ? 0? forming an angle ? 0? with the vertical as shown in figure The maximum desired altitude is ?R where R is the radius of the earth. The laws of...

A 2010 poll conducted by NBC asked respondents whowould win Super Bowl XLV in 2011. The responses by20,825 people are summarized in the following table. Team ......... Number of Votes Atlanta Falcons...

The following histogram summarizes the salaries (in $1,000,000s) for the 30 highest-paid players in the National Basketball Association (NBA) for the 2012 season (www.nba.com, data retrieved March...

Based on a Saint Index survey, when 1000 adults were asked to identify the most unpopular projects for their hometown, 54% included Wal-Mart among their choices. Consider the probability that among...

Listed below are the lead concentrations (in mg/g) measured in different Ayurveda medicines. Ayurveda is a traditional medical system commonly used in India. The lead concentrations listed here are...

A recent MBA graduate, Dara, has gained control over custodial accounts that her parents had established. Currently, her money is invested in four funds but she has identified several other funds as...

Professor Fair believes that extra time does not improve grades on exams. He randomly divided a group of 300 students into two groups and gave them all the same test. One group had exactly 1 hour in...

In a circuit with impressed voltage E having resistance R, inductance L, and capacitance C in parallel, the current i satisfies the differential equation Suppose C = 0.3 farads, R = 1.4 ohms, L = 1.7...

Social log-ins involve recommending or sharing an article that you read online. According to Janrain ("T. Wayne, One Log-In Catches on for Many Sites," The New York Times, May 2, 2011, p. B2), in the...

Use the data in ELEM94_95 to answer this question. The findings can be compared with those in Table 4.1. The dependent variable lavgsal is the log of average teacher salary and bs is the ratio of...

Suppose that a player draws a card at random from a pack of cards, and wins $15 if an Ace, king, Queen, or Jack is obtained, and otherwise wins the face value of the card in dollars. What is the...

John Daum and Chris Yin are star swimmers at a local college. They are preparing to compete at the NCAA Division II national championship meet, where they both have a good shot at earning a medal in...

The Streeter-Phelps model can be used to compute the dissolved oxygen concentration in a river below a point discharge of sewage (Figure), o = o s? ? k d L o /k d + k s ? k a (e ?kat? ? e ? (kd +...

Consider the monthly rent (Rent) of a home in Ann Arbor, Michigan, as a function of the number of bedrooms (Beds), the number of bathrooms (Baths), and square footage (Sqft). a. Access the data...

For the accompanying screen display, a simple random sample of size n = 40 was obtained from the population of duration times (seconds) of eruptions of the old Faithful geyser. a. What is the number...

Reconsider the model of Prob. 7.1-1. You are now to conduct sensitivity analysis by independently investigating each of the following six changes in the original model. For each change, use the...

An operation consists of two steps, of which the first can be made in n1 ways. If the first step is made in the ith way, the second step can be made in n2i ways. (a) Use a tree diagram to find a...

Assume a frequency curve for the following sets of data. What shape will the curve probably take? Use the following key: NO = normal NS = negatively skewed PS = positively skewed BI = bimodal RE =...

The National Fire Protection Association reported that house fires in the United States result in $6.8 billion in losses annually (National Fire Protection Association, September 2015). Suppose a...

A company operates four machines three shifts each day. From production records, the following data on the number of breakdowns are collected: Test the hypothesis (using a = 0.05) that breakdowns are...

The National Center for Health Statistics reported the following data on the number of children born in individual pregnancies in 1996 and 2006 (The World Almanac, 2010): a. Define a random variable...

Use the spreadsheet model constructed to answer Problem 1 to answer this problem. a. Construct a one-way data table with production volume as the column input and profit as the output. Breakeven...

In a random sample of 200 Phoenix residents who drive a domestic car, 165 reported wearing their seat belt regularly, while another sample of 250 Phoenix residents who drive a foreign car revealed...

The stepping-stone method is being used to solve a transportation problem. There is only one empty cell having a negative improvement index, and this index is 2. The stepping-stone path for this...

For a certain manufacturer, the production and sale of each additional unit yields an additional profit of $10. The sale of 1000 units yields a profit of $4000. (a) Find the profit equation. (b) Find...

Using principles from physics it can be shown that when a cable is hung between two poles, it takes the shape of a curve y = f(x) that satisfies the differential equation where p is the linear...