Use the information given and the eight-step approach to test the hypotheses. Let α = .05. Assume that the population is normally distributed. H0: μ = 7.82 Ha: μ < 7.82 n = 17 x̅ = 7.01 s = 1.69
> Construct a 90% confidence interval to estimate D from the following sample information. Assume the differences are normally distributed in the population.
> Construct a 98% confidence interval to estimate D from the following sample information. Assume the differences are normally distributed in the population. d̅ = 40.56, sd = 26.58, n = 22
> Use the data given to test the following hypotheses (α = .05). Assume the differences are normally distributed in the population. H0: D = 0 Ha: D ≠0
> Use the data given and a 1% level of significance to test the following hypotheses. Assume the differences are normally distributed in the population. H0: D = 0 Ha: D > 0
> Some studies have shown that in the United States, men spend more than women buying gifts and cards on Valentine’s Day. Suppose an analyst wants to test this hypothesis by randomly sampling 9 men and 10 women with comparable demographic characteristics f
> Use the following sample information to construct a 90% confidence interval for the difference in the two population means.
> A study was made to compare the costs of supporting a family of four Americans for a year in different foreign cities. The lifestyle of living in the United States on an annual income of $75,000 was the standard against which living in foreign cities was
> What is the difference in average daily hotel room rates between Minneapolis and New Orleans? Suppose we want to estimate this difference by taking hotel rate samples from each city and using a 98% confidence level. The data for such a study follow. Use
> Based on an indication that mean daily car rental rates may be higher for Boston than for Dallas, a survey of eight car rental companies in Boston is taken and the sample mean car rental rate is $47, with a sample standard deviation of $3. Further, suppo
> A valve manufacturer produces a butterfly valve composed of two semicircular plates on a common spindle that is used to permit flow in one direction only. The semicircular plates are supplied by a vendor with specifications that the plates be 2.37 millim
> According to the National Association of Colleges and Employers, the average hourly wage of an undergraduate college student working as a co-op is $17.27 and the average hourly wage of a college student working as an intern is $16.57. Assume that such wa
> Suppose a realtor is interested in comparing the asking prices of midrange homes in Peoria, Illinois, and Evansville, Indiana. The realtor conducts a small telephone survey in the two cities, asking the prices of midrange homes. A random sample of 21 lis
> Suppose you want to determine whether the average values for populations 1 and 2 are different, and you randomly gather the following data. Test your conjecture, using a probability of committing a Type I error of .01. Assume the population variances ar
> Suppose that for years the mean of population 1 has been accepted as the same as the mean of population 2 but that now population 1 is believed to have a greater mean than population 2. Letting α = .05 and assuming the populations have equa
> Use the following data and α = .10 to test the stated hypotheses. Assume x is normally distributed in the populations and the variances of the populations are approximately equal. H0: μ1 − μ2 =
> Use the data given and the eight-step process to test the following hypotheses. H0: μ1 − μ2 = 0 Ha: μ1 − μ2 Use a 1% level of significance, and assume that x is
> Two processes in a manufacturing line are performed manually: operation A and operation B. A random sample of 50 different assemblies using operation A shows that the sample average time per assembly is 8.05 minutes, with a population standard deviation
> Test the following hypotheses of the difference in population means by using the following data (α = .10) and the eight-step process. H0: μ1 − μ2 = 0 Ha: μ1 âˆ
> A manufacturing company produces valves in various sizes and shapes. One particular valve plate is supposed to have a tensile strength of 5 pounds per millimeter (lbs/mm). The company tests a random sample of 42 such valve plates from a lot of 650 valve
> According to a study several years ago by the Personal Communications Industry Association, the average cell phone user earns $62,600 per year. Suppose an analyst believes that the average annual earnings of a cell phone user are lower now, and he sets u
> According to Runzheimer International, the average cost of a domestic trip for business travelers in the financial industry is $1,250. Suppose another travel industry research company takes a random sample of 51 business travelers in the financial indust
> According to the U.S. Bureau of Labor Statistics, the average weekly earnings of a production worker in manufacturing in the United States as of October 2018 was $867.60. Suppose a labor analyst wants to test to determine whether this figure is still acc
> The American Express Retail Index states that the average U.S. household will spend $2,747 on home improvement projects this year. Suppose a large national home improvement company wants to test that figure in the West, theorizing that the average might
> In a recent year, published statistics by Drovers indicated that the average all-fresh retail beef price was $5.83 per pound. Suppose a survey of retailers is conducted this year to determine whether the price of all-fresh retail beef has increased. The
> One survey conducted by RHI Management Resources determined that the Lexus is the favorite luxury car for 25% of CFOs. Suppose a financial management association conducts its own survey of CFOs in an effort to determine whether this figure is correct. Th
> According to the U.S. Census Bureau, the average American generates 4.4 pounds of garbage per day. Suppose we believe that because of recycling and a greater emphasis on the environment, the figure is now lower. To test this notion, we take a random samp
> Downtime in manufacturing is costly and can result in late deliveries, backlogs, failure to meet orders, and even loss of market share. Suppose a manufacturing plant has been averaging 23 minutes of downtime per day for the past several years, but during
> The American Water Works Association reports that, on average, men use between 10 and 15 gallons of water daily to shave when they leave the water running. Suppose the following data are the numbers of gallons of water used in a day to shave by 12 random
> According to SquareFoot.com, the average Class A offiace space in Fort Worth is $31 per square foot. A large real-estate company wants to confirm this figure. The firm conducts a telephone survey of 95 Class A offices in Fort Worth and asks the office ma
> A study of pollutants showed that certain industrial emissions should not exceed 2.5 parts per million. You believe a particular company may be exceeding this average. To test this supposition, you randomly take a sample of nine air tests. The sample ave
> A local company installs natural-gas grills. As part of the installation, a ditch is dug tolay a small natural-gas line from the grill to the main line. On the average, the depth of these lines seems to run about 1 foot. The company claims that the depth
> Use the following data to construct a 99% confidence interval for μ. Assume x is normally distributed. What is the point estimate for μ?
> The Environmental Protection Agency releases figures on urban air soot in selected cities in the United States. For the city of St. Louis, the EPA claims that the average number of micrograms of suspended particles per cubic meter of air is 82. Suppose S
> A national publication reported that a college student living away from home spends, on average, no more than $15 per month on laundry. You believe this figure is too low and want to disprove the publication’s claim. To conduct the test, you randomly sel
> According to Gartner Inc., the second-largest share of the worldwide PC market is held by Hewlett-Packard with 21.7%. Suppose that a market researcher believes that Hewlett-Packard holds a higher share of the market in the western region of the United St
> Suppose the number of beds filled per day in a medium-sized hospital is normally distributed. A hospital administrator tells the board of directors that, on the average, at least 185 beds are filled on any given day. One of the board members believes tha
> A study of MBA graduates by Universum for the American Graduate Survey 1999 revealed that MBA graduates had several expectations of prospective employers beyond their base pay. In particular, according to the study 46% expect a performance-related bonus,
> A financial analyst watched a particular stock for several months. The price of this stock remained fairly stable during this time. In fact, the financial analyst claims that the variance of the price of this stock did not exceed $4 for the entire period
> Life insurance experts have been claiming that the average worker in the city of Cincinnati has no more than $25,000 of personal life insurance. An insurance analyst believes that this is not true and sets out to prove that the average worker in Cincinna
> A computer manufacturer estimates that its line of minicomputers has, on average, 8.4 days of downtime per year. To test this claim, an analyst contacts seven companies that own one of these computers and is allowed to access company computer records. It
> Highway engineers in Ohio are painting white stripes on a highway. The stripes are supposed to be approximately 10 feet long. However, because of the machine, the operator, and the motion of the vehicle carrying the equipment, considerable variation occu
> Brokers generally agree that bonds are a better investment during times of low interest rates than during times of high interest rates. A survey of executives during a time of low interest rates showed that 57% of them had some retirement funds invested
> A random sample of 15 items is taken, producing a sample mean of 2.364 with a sample variance of .81. Assume x is normally distributed and construct a 90% confidence interval for the population mean.
> According to Zero Population Growth, the average urban U.S. resident consumes 3.3 pounds of food per day. Is this figure accurate for rural U.S. residents? Suppose 64 rural U.S. residents are identified by a random procedure and their average consumption
> a) Use the data given to test the following hypotheses. H0 : μ = 1200 …..….…… Ha : μ > 1200 x̅ = 1215, n = 113 ……. σ = 100, α = .10 b) Use the p-value to obtain the results. c) Solve for the critical value required to reject the mean.
> According to a Gallup survey two years ago, 32% of American households use a computer or online financial program to manage their money. Suppose analysts believe that this figure has increased recently, and they test their theory by randomly sampling 80
> Solve for the value of beta in each of the following problems. a) H0: μ = 130 Ha: μ > 130 n = 75 σ = 12 α = .01 The alternative mean is actually 135. b) H0: p = .44 Ha: p < .44 n = 1095 α = .05 The alternative proportion is actually .42.
> Test the following hypotheses by using the information given and the eight-step approach. Let alpha be .01. Assume the population is normally distributed. H0: σ2 = 15.4 Ha: σ2 > 15.4 n = 18 s2 = 29.6
> For each of the following problems, use the eight-step approach to test the hypotheses. a) H0: p = .28 Ha: p > .28 n = 783 x = 230 α = .10 b) H0: p = .61 Ha: p ≠ .61 n = 401 p^ = .56 α = .05
> Use the information given and the eight-step approach to test the hypotheses. Let α = .01. H0: μ = 36 Ha: μ ≠ 36 n = 36 x̅ = 38.4 σ = 5.93
> A Harris poll was taken to determine which of 13 major industries are doing a good job of serving their customers. Among the industries rated most highly by Americans for serving their customers were computer hardware and software companies, car manufact
> The New York Stock Exchange recently reported that the average age of a female shareholder is 44 years. A broker in Chicago wants to know whether this figure is accurate for the female shareholders in Chicago. The broker secures a master list of sharehol
> If a random sample of 41 items produces x̅ = 128.4 and s = 20.6, what is the 98% confidence interval for μ? Assume x is normally distributed for the population. What is the point estimate?
> An alternative hypothesis is that p < .65. To test this hypothesis, a random sample of size 360 is taken. What is the probability of committing a Type II error if α = .05 and the alternative proportion is as follows? a) pa = .60 b) pa = .55 c) pa = .50
> Suppose a hypothesis states that the mean is exactly 50. If a random sample of 35 items is taken to test this hypothesis, what is the value of β if the population standard deviation is 7 and the alternative mean is 53? Use α = .01
> Use the data given to test the following hypotheses. Assume the data are normally distributed in the population. H0 : μ = 7.48 ……………… Ha : μ < 7.48 x̅ = 6.91, n = 24 ……… σ = 1.21, α = .01
> For Problem 9.38, use α = .05 and solve for the probability of committing a Type II error for the following possible true alternative means. a) μa = 98.5 b) μa = 98 c) μa = 97 d) μa = 96 e) What happens to the probability of committing a Type II error as
> Suppose a null hypothesis is that the population mean is greater than or equal to 100. Suppose further that a random sample of 48 items is taken and the population standard deviation is 14. For each of the following α values, compute the probability of c
> A company produces industrial wiring. One batch of wiring is specified to be 2.16 centimeters (cm) thick. A company inspects the wiring in seven locations and determines that, on the average, the wiring is about 2.16 cm thick. However, the measurements v
> A savings and loan averages about $100,000 in deposits per week. However, because of the way pay periods fall, seasonality, and erratic fluctuations in the local economy, deposits are subject to a wide variability. In the past, the variance for weekly de
> A manufacturing company produces bearings. One line of bearings is specified to be 1.64 centimeters (cm) in diameter. A major customer requires that the variance of the bearings be no more than .001 cm2. The producer is required to test the bearings befo
> Previous experience shows the variance of a given process to be 14. Business analysts are testing to determine whether this value has changed. They gather the following dozen measurements of the process. Use these data and α = .05 to test t
> Test each of the following hypotheses by using the given information. Assume the populations are normally distributed. a) H0: σ2 = 20 Ha: σ2 > 20 α = .05, n = 15, s2 = 32 b. H0: σ2 = 8.5 Ha: σ2 ≠ 8.5 α = .10, n = 22, s2 = 17 c) H0: σ2 = 45 Ha: σ2 < 45 α
> Assuming x is normally distributed, use the following information to compute a 90% confidence interval to estimate μ.
> A random sample of size 39 is taken from a population of 200 members. The sample mean is 66 and the population standard deviation is 11. Construct a 96% confidence interval to estimate the population mean. What is the point estimate of the population mea
> 1. A researcher wants to estimate the difference in the means of two populations. A random sample of 40 items from the first population results in a sample mean of 433 with a population standard deviation of 112. A random sample of 50 items from the seco
> 21. A researcher is testing a hypothesis of a single mean. The critical z value for ( = .05 and a two-tailed test is ± 1.96. The observed z value from sample data is -1.91. The decision made by the researcher based on this information is to _____________
> 11. Power is equal to _______________. 12. Whenever hypotheses are established such that the alternative hypothesis is directional, then the researcher is conducting a _______________-tailed test. 13. A _______________-tailed test is non-directional. 14.
> 1. The first step in testing a hypothesis is to establish a(n) _______________ hypothesis and a(n) _______________ hypothesis. 2. In testing hypotheses, the researcher initially assumes that the _______________ hypothesis is true. 3. The region of the di
> 41. The observed value of chi-square in problem 39 is ______________________. 42. The decision reached for problem 39 is _______________. 43. The null hypothesis for a test is H0: ( = 30. The population standard deviation is known to be 0.63. A one-taile
> 31. A political scientist want to statistically test the null hypothesis that her candidate for governor is currently carrying at least 57% of the vote in the state. She has her assistants randomly sample 550 eligible voters in the state by telephone and
> 23. Suppose we want to construct a confidence interval to estimate a population variance. A sample variance is computed from a sample of 14 items. To construct a 95% confidence interval, the chi-square table values are _______________ and _______________
> 11. The t test was developed by _______________. 12. In order to find values in the t distribution table, you must convert the sample size or sizes to _______________. 13. The table t value associated with 10 degrees of freedom and used to compute a 95%
> 13. In conducting multiple comparisons with unequal sample sizes with techniques presented in chapter 11 of the text, you would use which procedure? __________________ 14. Sup1pose the following data are taken as samples from three populations and that a
> 1. A plan for testing hypotheses in which the researcher either controls or manipulates one or more variables is called a(n) ______________________________________. 2. A variable that is either controlled or manipulated is called a(n) ___________________
> 33. The confidence interval computed for the problem in question 29 is _______________. 34. A researcher is interested in estimating the difference in two populations proportions. A sample of 1000 from each population results in sample proportions of .61
> 21. A researcher wants to conduct a before/after study on 13 subjects to determine if a treatment results in higher scores. The hypotheses are: Ho: D = 0 Ha: D Scores are obtained on the subjects both before and after the treatment. After subtracting th
> 11. Using the information from question 9, the observed value of z is _______________. 12. Using the results determined in question 10 and 11, the decision is to _______________ the null hypothesis. 13. A researcher is interested in testing to determine
> 1. When a statistic taken from the sample is used to estimate a population parameter, it is called a(n) _______________ estimate. 2. When a range of values is used to estimate a population parameter, it is called a(n) _______________ estimate. 3. The z v
> The furniture division of International Woodworking purchases timber and makes tables, chairs, and other wood furniture. Most of the timber is purchased from the Port Angeles Mill, also a division of International Woodworking. The furniture division and
> Prem International has two large subsidiaries, Oil and Chemical. Oil is an oil-refining entity, and its main product is petrol. Chemical produces and sells a variety of chemical products. Chemical owns a polystyrene processing plant next to Oilâ
> Avra Valley Services has two divisions, Computer Services and Management Advisory Services. Both divisions work for external customers and, in addition, work for each other. Fees earned by Computer Services from external customers were $400 000 in 2017.
> Automotive parts company Mopar implemented a new inventory management system costing $1.5 million. Mopar distributed parts from three central and 11 regional warehouses to hundreds of parts dealers. The entity filled orders for approximately 1 million li
> Budget Cupboards produces kitchen and bathroom cupboards that incorporate unusual functions, such as specialty drawers for knives and kitchen tools, and kitchen appliance holders that pop up from under the counter top. Competition in this industry has re
> Cairns Legal Services is part of a larger not-for-profit organisation (Capricorn Resource Centre) that provides free legal and job placement services and houses a food bank for qualified clients. Last year’s costs for 5000 visits to leg
> Suppose the Tasmanian government decided to preserve some beautiful caves in the southwestern part of the state. To defray the cost of preservation, the Tasmanian state tourism managers decided to open the caves to guided tours. To prepare the caves for
> The accountants at French Perfumery decided to increase the price of a scent called Breezy by 10%, from $6 per bottle to $6.60. French’s accountants expect the 10 per cent price increase to reduce unit sales by 20 per cent. Current sales are 200 000 bott
> Fancy Fleece developed a new outdoor wear fleece fabric that is both wind and water resistant, but retains a soft and fuzzy feel. The research and development process was more expensive than Fancy’s managers anticipated, and the materials in the fabric a
> Bainbridge University offers an MBA degree that is widely respected around the world. The tuition for the program has always covered the costs of the program until a recent recession increased the sensitivity of students to the cost of tuition. The busin
> If fixed costs are included in the marked up costs used in setting cost-based prices, a problem may occur when demand declines. Describe this problem.
> Hanson & Daughters produces a premium label apple juice to wholesalers at a current price of $7 per 5-litre container. Costs for a recent month, in which 100Â 000 5-litre containers were produced and sold, appear on following page: Hanso
> Transrapid is a new magnetically levitated train being developed to run between major cities in Germany at a speed of 500 kilometres per hour. Engineers developed a system with trains departing every 10 minutes. Suppose Transrapid asked you to research c
> Frosty Treats, a boutique ice cream shop, has asked your advice in setting pricing policies. Frosty Treats manager has collected information about prices and sales over the last four years. Required (a) Explain how you would use the prices and sales inf
> Suppose the owner of Haywood Ceramics needs to raise prices to stay in business, but is concerned that raising prices would result in a death spiral. To avoid a decline in sales, the owner is considering sending letters to her customers explaining why th
> Consider the Dublin Shirt Company in comprehensive example 1 and the additional material provided below. Two recent developments that may have an impact on the company should be Noted. First, in the present climate, The Dublin Shirt Company can only affo
> Burton Turner and Short Whittum live in a small town in northern Queensland. They both own petrol stations and provide fuel and engine repair services for the area. The town is somewhat isolated, and during the wet months it is sometimes difficult to tra
> Suppose you are having a conversation with Sandy, another student in this course. Sandy is confused about the differences and similarities between target costing and kaizen costing. Another student, Kevin, overhears your conversation with Sandy and insis
> Budget Cupboards produces kitchen and bathroom cupboards that incorporate unusual functions, such as specialty drawers for knives and kitchen tools, and kitchen appliance holders that pop up from under the counter top. Competition in this industry has re
> Tania Wells owns and operates Gym Gear R Us, a growing internet business that specialises in the sale of gymwear for men, women and children. Tania designs her products but has them manufactured offshore. Since starting the business three years ago, she
> John Gold has owned and operated Heritage Jewellery Store for a number of years. He uses the standard mark-up of 300 per cent (known as a triple key in this industry) and uses an average cost that includes an allocation of overhead as the cost base. Late
