A national survey of insurance offices was taken, resulting in a random sample of 245 companies. Of these 245 companies, 189 responded that they were going to purchase new software for their offices in the next year. Construct a 90% confidence interval to estimate the population proportion of insurance offices that intend to purchase new software during the next year.
> The only time you change the original cash flow diagram in problems involving uniform series cash flows is when the: (a) payment period is longer than the compounding period (b) payment period is equal to the compounding period (c) payment period is sho
> An interest rate of 18% per year, compounded continuously, is closest to an effective: (a) 1.51% per quarter (b) 4.5% per quarter (c) 4.6% per quarter (d) 9% per 6 months
> An interest rate of 2% per month is the same as: (a) 24% per year, compounded monthly (b) a nominal 24% per year, compounded monthly (c) an effective 24% per year, compounded monthly (d) Both (a) and (b)
> Lego Group in Bellund, Denmark manufactures Lego toy construction blocks. The company is considering two methods for producing special-purpose Lego parts. Method 1 will have an initial cost of $400,000, an annual operating cost of $140,000, and a life of
> The Briggs and Stratton Commercial Division designs and manufactures small engines for golf turf maintenance equipment. A robotics-based testing system with support equipment will ensure that their new signature guarantee program entitled â€&#
> Where do CFOs get their money news? According to Robert Half International, 47% get their money news from newspapers, 15% get it from communication/colleagues, 12% get it from television, 11% from the Internet, 9% from magazines, 5% from radio, and 1% do
> A large manufacturing company investigated the service it received from suppliers and discovered that, in the past, 32% of all materials shipments were received late. However, the company recently installed a just-in-time system in which suppliers are li
> Eighteen percent of U.S.-based multinational companies provide an allowance for personal long-distance calls for executives living overseas, according to the Institute for International Human Resources and the National Foreign Trade Council. Suppose a bu
> a) Use the data given to test the following hypotheses. H0 : μ = 25 ………………………. Ha : μ ≠ 25 x̅ = 28.1, n = 57 ……….. σ = 8.46, α = .01 b) Use the p-value to reach a statistical conclusion. c) Using the critical value method, what are the critical sample m
> A survey was undertaken by Bruskin/Goldring Research for Quicken to determine how people plan to meet their financial goals in the next year. Respondents were allowed to select more than one way to meet their goals. Thirty-one percent said that they were
> A study by Hewitt Associates showed that 79% of companies offer employees flexible scheduling. Suppose a business analyst believes that in accounting firms this figure is lower. The analyst randomly selects 415 accounting firms and through interviews det
> Independent Insurance Agents of America conducted a survey of insurance consumers and discovered that 48% of them always reread their insurance policies, 29% sometimes do, 16% rarely do, and 7% never do. Suppose a large insurance company invests consider
> Suppose you are testing H0: p = .29 versus Ha: p ≠ .29. A random sample of 740 items shows that 207 have this characteristic. With a .05 probability of committing a Type I error, test the hypothesis. For the p-value method, what is the probability of the
> Suppose you are testing H0: p = .63 versus Ha: p < .63. For a random sample of 100 people, x = 55, where x denotes the number in the sample that have the characteristic of interest. Use a .01 level of significance to test this hypothesis.
> Suppose you are testing H0: p = .45 versus Ha: p > .45. A random sample of 310 people produces a value of p^ = .465. Use α = .05 to test this hypothesis.
> Suppose the following data are selected randomly from a population of normally distributed values. Construct a 95% confidence interval to estimate the population mean.
> According to a National Public Transportation survey, the average commuting time for people who commute to a city with a population of 1 to 3 million is 19.0 minutes. Suppose a business analyst lives in a city with a population of 2.4 million and wants t
> According to data released by the World Bank, the mean PM10 (particulate matter) concentration for the city of Kabul, Afghanistan, in 1999 was 46. Suppose that because of efforts to improve air quality in Kabul, increases in modernization, and efforts to
> Based on population figures and other general information on the U.S. population, suppose it has been estimated that, on average, a family of four in the United States spends about $1,135 annually on dental procedures. Suppose further that a regional den
> Major cities around the world compete with each other to attract new businesses. Some of the criteria that businesses use to judge cities as potential locations for their headquarters might include the labor pool; the environment, including work, governm
> In each of the following scenarios, tell if the analyst has committed a Type I error, committed a Type II error, or made a correct decision. a) An analyst is testing to determine if .31 of all families own more than one car. His null hypothesis is that t
> Suppose that in past years the average price per square foot for warehouses in the United States has been $32.28. A national real-estate investor wants to determine whether that figure has changed now. The investor hires a business analyst who randomly s
> Suppose a study reports that the average price for a gallon of self-serve regular unleaded gasoline is $2.76. You believe that the figure is higher in your area of the country. You decide to test this claim for your part of the United States by randomly
> A hole-punch machine is set to punch a hole 1.84 centimeters in diameter in a strip of sheet metal in a manufacturing process. The strip of metal is then creased and sent on to the next phase of production, where a metal rod is slipped through the hole.
> The following data (in pounds), which were selected randomly from a normally distributed population of values, represent measurements of a machine part that is supposed to weigh, on average, 8.3 pounds. Use these data and α = .01 to test t
> The following data were gathered from a random sample of 11 items. Use these data and a 5% level of significance to test the following hypotheses, assuming that the data come from a normally distributed population. H0 : μ = 1160 â
> Suppose a random sample of turkey prices is taken from across the nation in an effort to estimate the average turkey price per pound in the United States. Shown here is the Minitab output for such a sample. Examine the output. What is the point estimate?
> A random sample of 51 items is taken, with x̅ = 58.42 and s2 = 25.68. Use these data to test the following hypotheses, assuming you want to take only a 1% risk of committing a Type I error and that x is normally distributed. H0 : μ = 60 ………… Ha : μ < 60
> A random sample of size 20 is taken, resulting in a sample mean of 16.45 and a sample standard deviation of 3.59. Assume x is normally distributed and use this information and α = .05 to test the following hypotheses. H0 : μ = 16 ………………. Ha : μ ≠ 16
> The American Water Works Association estimates that the average person in the United States uses 123 gallons of water per day. Suppose some analysts believe that more water is being used now and want to test to determine whether this is so. They randomly
> According to HowtoAdvice.com, the average price charged to a customer to have a 12′ by 18′ wall-to-wall carpet shampoo cleaned is about $50. Suppose that a start-up carpet-cleaning company believes that in the region i
> According to a report released by CIBC entitled “Women Entrepreneurs: Leading the Charge,” the average age for Canadian businesswomen in 2008 was 41. In the report, there was some indication that analysts believed that this mean age will increase. Suppos
> Read each of the following statements. Assuming that statistical hypotheses are set up to test them, classify each as a one-tailed or a two-tailed test. a) Maritz Marketing Research reports that 42% of all adults seek advice from others in selecting a la
> What proportion of all American workers drive their cars to work? Suppose a poll of American workers is taken in an effort to answer that question, and the Minitab output shown here is an analysis of the data from the poll. Explain the meaning of the out
> Suppose a business analyst wants to estimate the average age of a person who is a first- time home buyer. A random sample of first-time home buyers is taken and their ages are ascertained. The Minitab output shown here is an analysis of that data. Study
> A company has developed a new light bulb that seems to burn longer than most residential bulbs. To determine how long these bulbs burn, the company randomly selects a sample of these bulbs and burns them in the laboratory. The Excel output shown here is
> A soft drink company produces a cola in a 12-ounce can. Even though their machines are set to fill the cans with 12 ounces, variation due to calibration, operator error, and other things sometimes precludes the cans having the correct fill. To monitor th
> According to the U.S. Census Bureau, the average travel time to work in Philadelphia is 31.5 minutes. Suppose a business analyst wants to estimate the average travel time to work in Cleveland using a 95% level of confidence. A random sample of 45 Clevela
> A study of 1000 adult Canadians was undertaken in an effort to obtain information about Canadian shopping habits. One of the results of this survey was that 23% often buy items that are not on their shopping list but catch their eye. Use this study resul
> The price of a head of iceberg lettuce varies greatly with the season and the geographic location of a store. During February a business analyst contacts a random sample of 39 grocery stores across the United States and asks the produce manager of each t
> A national survey showed that Hillshire Farm Deli Select cold cuts were priced, on the average, at $5.20 per pound. Suppose a national survey of 23 retail outlets was taken and the price per pound of Hillshire Farm Deli Select cold cuts was ascertained.
> A national magazine marketing firm attempts to win subscribers with a mail campaign that involves a contest using magazine stickers. Often when people subscribe to magazines in this manner they sign up for multiple magazine subscriptions. Suppose the mar
> A research firm has been asked to determine the proportion of all restaurants in the state of Ohio that serve alcoholic beverages. The firm wants to be 98% confident of its results but has no idea of what the actual proportion is. The firm would like to
> A regional survey of 560 companies asked the vice president of operations how satisfied he or she was with the software support received from the computer staff of the company. Suppose 33% of the 560 vice presidents said they were satisfied. Construct a
> A survey of 77 commercial airline flights of under 2 hours resulted in a sample average late time for a flight of 2.48 minutes. The population standard deviation was 12 minutes. Construct a 95% confidence interval for the average time that a commercial f
> According to a survey by Runzheimer International, the average cost of a fast-food meal (quarter-pound cheeseburger, large fries, medium soft drink, excluding taxes) in Seattleis $4.82. Suppose this figure was based on a sample of 27 different establishm
> A movie theater has had a poor accounting system. The manager has no idea how many large containers of popcorn are sold per movie showing. She knows that the amounts vary by day of the week and hour of the day. However, she wants to estimate the overall
> A national survey of companies included a question that asked whether the company had at least one bilingual telephone operator. The sample results of 90 companies follow (Y denotes that the company does have at least one bilingual operator; N denotes th
> A meat-processing company in the Midwest produces and markets a package of eight small sausage sandwiches. The product is nationally distributed, and the company is interested in knowing the average retail price charged for this item in stores across the
> An entrepreneur wants to open an appliance repair shop. She would like to know about what the average home repair bill is, including the charge for the service call for appliance repair in the area. She wants the estimate to be within $20 of the actual f
> A national survey on telemarketing was undertaken. One of the questions asked was: How long has your organization had a telemarketing operation? Suppose the following data represent some of the answers received to this question (in years). Suppose furthe
> According to a survey by Topaz Enterprises, a travel auditing company, the average error by travel agents is $128. Suppose this figure was obtained from a random sample of 41 travel agents and the sample standard deviation is $21. What is the point estim
> Is the environment a major issue with Americans? To answer that question, an analyst conducts a survey of 1255 randomly selected Americans. Suppose 714 of the sampled people replied that the environment is a major issue with them. Construct a 95% confide
> A national beauty spa chain wants to estimate the number of times per year a woman has her nails done at one of their spas if she uses one at least once a year. The chain’s analyst estimates that, of those women who use a beauty spa at least once a year
> A random sample of small-business managers was given a leadership-style questionnaire. The results were scaled so that each manager received a score for initiative. Suppose the following data are a random sample of these scores. Assuming σ is
> What is the average length of a company’s policy book? Suppose policy books are sampled from 45 medium-sized companies. The average number of pages in the sample books is 213, and the population standard deviation is 48. Use this information to construct
> Use the data in Problem 8.53 to construct a 99% confidence interval to estimate the population variance for the number of diapers used during a 24-hour period for one-month- olds. How could information about the population variance be used by a manufactu
> Suppose you want to estimate the proportion of cars that are sport utility vehicles (SUVs) being driven in Kansas City, Missouri, at rush hour by standing on the corner of I-70 and I-470 and counting SUVs. You believe the figure is no higher than .40. If
> A community health association is interested in estimating the average number of maternity days women stay in the local hospital. A random sample is taken of 36 women who had babies in the hospital during the past year. The following numbers of maternity
> In planning both market opportunity and production levels, being able to estimate the size of a market can be important. Suppose a diaper manufacturer wants to know how many diapers a one-month-old baby uses during a 24-hour period. To determine this usa
> Determine the sample size necessary under the following conditions. a) To estimate μ with σ = 44, E = 3, and 95% confidence. b) To estimate μ with a range of values from 20 to 88 with E = 2 and 90% confidence. c) To estimate p with p unknown, E = .04, an
> Use the following data to construct 90% and 95% confidence intervals to estimate the population variance. Assume the data come from a normally distributed population.
> Construct 90%, 95%, and 99% confidence intervals to estimate μ from the following data. State the point estimate. Assume the data come from a normally distributed population.
> Use the following data to construct 80%, 94%, and 98% confidence intervals to estimate μ. Assume that σ is 7.75. State the point estimate.
> What proportion of shoppers at a large appliance store actually makes a large-ticket purchase? To estimate this proportion within 10% and be 95% confident of the results, how large a sample should you take? Assume you have no idea what proportion of all
> What proportion of secretaries of Fortune 500 companies has a personal computer at his or her workstation? You want to answer this question by conducting a random survey. How large a sample should you take if you want to be 95% confident of the results a
> Suppose a production facility purchases a particular component part in large lots from a supplier. The production manager wants to estimate the proportion of defective parts received from this supplier. She believes the proportion defective is no more th
> A group of investors wants to develop a chain of fast-food restaurants. In determining potential costs for each facility, they must consider, among other expenses, the average monthly electric bill. They decide to sample some fast-food restaurants curren
> The average total dollar purchase at a convenience store is less than that at a supermarket. Despite smaller-ticket purchases, convenience stores can still be profitable because of the size of operation, the volume of business, and the markup. A business
> Suppose you have been following a particular airline stock for many years. You are interested in determining the average daily price of this stock in a 10-year period and you have access to the stock reports for these years. However, you do not want to a
> A bank officer wants to determine the amount of the average total monthly deposits per customer at the bank. He believes an estimate of this average amount using a confidence interval is sufficient. How large a sample should he take to be within $200 of
> Determine the sample size necessary to estimate p for the following information. a) E = .02, p is approximately .40, and confidence level is 96% b) E is to be within .04, p is unknown, and confidence level is 95% c) E is to be within 5%, p is approximate
> Determine the sample size necessary to estimate μ for the following information. a) σ = 36 and E = 5 at 95% confidence b) σ = 4.13 and E = 1 at 99% confidence c) Values range from 80 to 500, error is to be within 10, and the confidence level is 90% d) Va
> Suppose a random sample of 14 people 30–39 years of age produced the household incomes shown here. Use these data to determine a point estimate for the population variance of household incomes for people 30–39 years of
> A manufacturing plant produces steel rods. During one production run of 20,000 such rods, the specifications called for rods that were 46 centimeters in length and 3.8 centimeters in width. Fifteen of these rods comprising a random sample were measured f
> The Interstate Conference of Employment Security Agencies says the average workweek in the United States is down to only 35 hours, largely because of a rise in part-time workers. Suppose this figure was obtained from a random sample of 20 workers and tha
> Use the following sample data to estimate the population variance. Produce a point estimate and a 98% confidence interval. Assume the data come from a normally distributed population.
> For each of the following sample results, construct the requested confidence interval. Assume the data come from normally distributed populations. a) n = 12, x̅ = 28.4, s2 = 44.9; 99% confidence for σ2 b) n = 7, x̅ = 4.37, s = 1.24; 95% confidence for σ2
> Suppose a survey of 275 executives is taken in an effort to determine what qualities are most important for an effective CEO to possess. The survey participants are offered several qualities as options, one of which is “communication.” One hundred twenty
> A small lawnmower company produced 1500 lawnmowers in 2008. In an effort to determine how maintenance-free these units were, the company decided to conduct a multiyear study of the 2008 lawnmowers. A sample of 200 owners of these lawnmowers was drawn ran
> A random sample of size 70 is taken from a population that has a variance of 49. The sample mean is 90.4. What is the point estimate of μ? Construct a 94% confidence interval for μ.
> A random sample of 81 items is taken, producing a sample mean of 47. The population standard deviation is 5.89. Construct a 90% confidence interval to estimate the population mean.
> According to Runzheimer International, in a survey of relocation administrators 63% of all workers who rejected relocation offers did so for family considerations. Suppose this figure was obtained by using a random sample of the files of 672 workers who
> For a random sample of 36 items and a sample mean of 211, compute a 95% confidence interval for μ if the population standard deviation is 23.
> Use the following information to construct the confidence intervals specified to estimate μ. a) 95% confidence for x̅ = 25, σ = 3.5, and n = 60 b) 98% confidence for x̅ = 119.6, σ = 23.89, and n = 75 c) 90% confidence for x̅ = 3.419, σ = 0.974, and n = 3
> 1. Among other things, the Container Store has grown and flourished because of strong customer relationships, which include listening to customer needs, providing products that meet customer needs, having salespeople who understand both customer needs an
> The successful Clarkson knife-gate valve contains a wafer that is thin and light. Yet, the wafer is so strong it can operate with up to 150 pounds-per-square-inch (psi) of pressure on it, making it much stronger than those of competing brands. Suppose Em
> 1. Suppose a fast-food analyst is interested in determining if there is a difference between Denver and Chicago in the average price of a comparable hamburger. There is some indication, based on information published by Burger Week, that the average pric
> 1. Many proportions were generated in the focus groups and market research that were conducted for this project, including the proportion of the market that is Hispanic, the proportion of Hispanic grocery shoppers that are women, the proportion of chip p
> Suppose you are using a completely randomized design to study some phenomenon. There are five treatment levels and a total of 55 people in the study. Each treatment level has the same sample size. Complete the following ANOVA.
> Compute a one-way ANOVA on the following data. 1 …………….….. 2 27 ………….… 22 31 ….……….… 27 31 …...…….… 25 29 ………….… 23 30 ………….… 26 27 ………….… 27 28 ………….… 23 Determine the observed F value. Compare it to the critical table F value and decide whether to rej
> Develop a one-way ANOVA on the following data. Determine the observed F value. Compare it to the critical F value and decide whether to reject the null hypothesis. Use a 1% level of significance.
> Discuss the following Minitab output. Analysis of Variance Means
> What proportion of commercial airline pilots are more than 40 years of age? Suppose a business analyst has access to a list of all pilots who are members of the Commercial Airline Pilots Association. If this list is used as a frame for the study, she can
> Study the following Minitab output. Determine whether there are any significant effects and discuss the results. What kind of design was used and what was the size of it? Analysis of Variance
> Interpret the following Excel output. Discuss the structure of the experimental design and any significant effects. Alpha is .05. ANOVA: Two-Factor Without Replication
> Study the following Minitab output and graph. Discuss the meaning of the output. Analysis of Variance for Dependent Variable
> Following is Excel output for an ANOVA problem. Describe the experimental design. The given value of alpha was .05. Discuss the output in terms of significant findings. ANOVA: Two-Factor Without Replication
> Analyze the following Minitab output. Describe the design of the experiment. Using α = .05, determine whether there are any significant effects; if so, explain why. Discuss any other ramifications of the output. Analysis of Variance
> Are some office jobs viewed as having more status than others? Suppose a study is conducted in which eight unemployed people are interviewed. The people are asked to rate each of five positions on a scale from 1 to 10 to indicate the status of the positi
