Essentials Of Statistics For Business & Economics
9th Edition
ISBN: 9780357045435
Author: David R. Anderson, Dennis J. Sweeney, Thomas A. Williams, Jeffrey D. Camm, James J. Cochran
Publisher: South-Western College Pub
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Chapter 8.5, Problem 47E
Speeding Drivers. In 2017, ABC News reported that 58% of U.S. drivers admit to speeding. Suppose that a new satellite technology can instantly measure the speed of any vehicle on a U.S. road and determine whether the vehicle is speeding, and this satellite technology was used to take a sample of 20,000 vehicles at 6:00 p.m. EST on a recent Tuesday afternoon. Of these 20,000 vehicles, 9,252 were speeding.
- a. What is the sample proportion of vehicles on U.S. roads that speed?
- b. Using 99% confidence, what is the margin of error?
- c. Using the results from parts (a) and (b), develop the 99% confidence
interval estimate of the proportion of vehicles on U.S. roads that speed. - d. What does the confidence interval in part (c) lead you to conclude about the ABC News report?
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Chapter 8 Solutions
Essentials Of Statistics For Business & Economics
Ch. 8.1 - A simple random sample of 40 items resulted in a...Ch. 8.1 - 2. A simple random sample of 50 items from a...Ch. 8.1 - A simple random sample of 60 items resulted in a...Ch. 8.1 - 4. A 95% confidence interval for a population mean...Ch. 8.1 - Data were collected on the amount spent by 64...Ch. 8.1 - Travel Taxes. In an attempt to assess total daily...Ch. 8.1 - Cost of Dog Ownership. Money reports that the...Ch. 8.1 - Studies show that massage therapy has a variety of...Ch. 8.1 - Cost to Repair Fire Damage. The mean cost to...Ch. 8.1 - 10. Costs are rising for all kinds of medical...
Ch. 8.2 - For a t distribution with 16 degrees of freedom,...Ch. 8.2 - Find the t value(s) for each of the following...Ch. 8.2 - The following sample data are from a normal...Ch. 8.2 - A simple random sample with n = 54 provided a...Ch. 8.2 - 15. Sales personnel for Skillings Distributors...Ch. 8.2 - Years to Bond Maturity. A sample containing years...Ch. 8.2 - Quality Ratings of Airports. The International Air...Ch. 8.2 - Unemployment in Older Workers. Older people often...Ch. 8.2 - Meal Cost in Hong Kong. The mean cost of a meal...Ch. 8.2 - Automobile Insurance Premiums. The average annual...Ch. 8.2 - Telemedicine. Health insurers are beginning to...Ch. 8.2 - Movie Ticket Sales. Marvel Studios motion picture...Ch. 8.3 - 23. How large a sample should be selected to...Ch. 8.3 - The range for a set of data is estimated to be 36....Ch. 8.3 - Refer to the Scheer Industries example in Section...Ch. 8.3 - Gasoline Prices. The U.S. Energy Information...Ch. 8.3 - Salaries of Business Graduates. Annual starting...Ch. 8.3 - 28. Many medical professionals believe that eating...Ch. 8.3 - 29. Customers arrive at a movie theater at the...Ch. 8.3 - Prob. 30ECh. 8.4 - A simple random sample of 400 individuals provides...Ch. 8.4 - A simple random sample of 800 elements generates a...Ch. 8.4 - In a survey, the planning value for the population...Ch. 8.4 - At 95% confidence, how large a sample should be...Ch. 8.4 - Health-Care Survey. In the spring of 2017, the...Ch. 8.4 - According to statistics reported on CNBC, a...Ch. 8.4 - Voter Sentiment. One of the questions Rasmussen...Ch. 8.4 - 38. According to Franchise business review, over...Ch. 8.4 - In 16% of all homes with a stay-at-home parent,...Ch. 8.4 - Prob. 40ECh. 8.4 - Driver’s License Rates. Fewer young people are...Ch. 8.4 - 42. A poll for the presidential campaign sampled...Ch. 8.4 - 43. The Pew Research Center Internet Project,...Ch. 8.5 - Federal Tax Return Errors. Suppose a sample of...Ch. 8.5 - Federal Government Employee Sick Hours. According...Ch. 8.5 - Web Browser Satisfaction. Internet users were...Ch. 8.5 - Speeding Drivers. In 2017, ABC News reported that...Ch. 8 - 44. A sample survey of 54 discount brokers showed...Ch. 8 - 45. A survey conducted by the American Automobile...Ch. 8 - 46. The 92 million Americans of age 50 and over...Ch. 8 - Healthy Sleep Duration. The Centers for Disease...Ch. 8 - The Health Care Cost Institute tracks health care...Ch. 8 - Obesity. Obesity is a risk factor for many health...Ch. 8 - Prob. 54SECh. 8 - 51. In developing patient appointment schedules, a...Ch. 8 - Prob. 56SECh. 8 - 53. The National Center for Education Statistics...Ch. 8 - A USA Today/CNN/Gallup survey of 369 working...Ch. 8 - Social Media Usage. The Pew Research Center has...Ch. 8 - Prob. 60SECh. 8 - The Centers for Disease Control reported the...Ch. 8 - A well-known bank credit card firm wishes to...Ch. 8 - Credit Card Ownership. Credit card ownership...Ch. 8 - 60. Although airline schedules and cost are...Ch. 8 - Driving Speeds. Huston Systems Private Limited...Ch. 8 - Prob. 66SECh. 8 - Prob. 67SECh. 8 - Prob. 68SECh. 8 - Young Professional Magazine Young Professional...Ch. 8 - Gulf Real Estate Properties Gulf Real Estate...Ch. 8 - Metropolitan Research, Inc.
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