Essentials of Statistics for Business and Economics
9th Edition
ISBN: 9780357118191
Author: David R. Anderson, Dennis J. Sweeney, Thomas A. Williams
Publisher: Cengage Learning US
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Chapter 6, Problem 53SE
Do you dislike waiting in line? Supermarket chain Kroger has used computer simulation and information technology to reduce the average waiting time for customers at 2300 stores. Using a new system called QueVision, which allows Kroger to better predict when shoppers will be checking out, the company was able to decrease average customer waiting time to just 26 seconds (InformationWeek website and The Wall Street Journal website, January 5, 2015).
- a. Assume that Kroger waiting times are exponentially distributed. Show the
probability densityfunction of waiting time at Kroger. - b. What is the probability that a customer will have to wait between 15 and 30 seconds?
- c. What is the probability that a customer will have to wait more than 2 minutes?
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Chapter 6 Solutions
Essentials of Statistics for Business and Economics
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Ch. 6.2 - Given that z is a standard normal random variable,...Ch. 6.2 - Given that z is a standard normal random variable,...Ch. 6.2 - 13. Given that z is a standard normal random...Ch. 6.2 - Given that z is a standard normal random variable,...Ch. 6.2 - Given that z is a standard normal random variable,...Ch. 6.2 - Given that z is a standard normal random variable,...Ch. 6.2 - Height of Dutch Men. Males in the Netherlands are...Ch. 6.2 - Large-Cap Domestic Stock Fund. The average return...Ch. 6.2 - Automobile Repair Costs. Automobile repair costs...Ch. 6.2 - Gasoline Prices. Suppose that the average price...Ch. 6.2 - Mensa Membership. A person must score in the upper...Ch. 6.2 - Television Viewing. Suppose that the mean daily...Ch. 6.2 - Time to Complete Final Exam. The time needed to...Ch. 6.2 - Labor Day Travel Costs. The American Automobile...Ch. 6.2 - Household Income in Maryland. According to Money...Ch. 6.3 - A binomial probability distribution has p=.20 and...Ch. 6.3 - Assume a binomial probability distribution has p =...Ch. 6.3 - Adults Who Smoke. Although studies continue to...Ch. 6.3 - Americans Who Believe Global Warming Is Occurring....Ch. 6.3 - Playing Video Games. Suppose that of those...Ch. 6.3 - Visitors to Rocky Mountain National Park. Rocky...Ch. 6.4 - Consider the following exponential probability...Ch. 6.4 - 33. Consider the following exponential probability...Ch. 6.4 - 34. Battery life between charges for the Motorola...Ch. 6.4 - 35. The time between arrivals of vehicles at a...Ch. 6.4 - 36. Comcast Corporation is the largest cable...Ch. 6.4 - 37. Wendy’s restaurant has been recognized for...Ch. 6.4 - 38. The Boston Fire Department receives 911 calls...Ch. 6 - 39. A business executive, transferred from Chicago...Ch. 6 - NCAA Scholarships. The NCAA estimates that the...Ch. 6 - Production Defects. Motorola used the normal...Ch. 6 - Bringing Items to a Pawnshop. One indicator of the...Ch. 6 - Amazon Alexa App Downloads. Alexa is the popular...Ch. 6 - Service Contract Offer. Ward Doering Auto Sales is...Ch. 6 - Wedding Costs. The XO Group Inc. conducted a 2015...Ch. 6 - College Admissions Test Scores. Assume that the...Ch. 6 - College Graduates Starting Salaries. According to...Ch. 6 - 48. A machine fills containers with a particular...Ch. 6 - Multiple-Choice Exam. Consider a multiple-choice...Ch. 6 - Playing Blackjack. A blackjack player at a Las...Ch. 6 - Mean Time Between Failures. The mean time between...Ch. 6 - The website for the Bed and Breakfast Inns of...Ch. 6 - Do you dislike waiting in line? Supermarket chain...Ch. 6 - Prob. 54SE
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