Introduction to Statistics and Data Analysis
5th Edition
ISBN: 9781305115347
Author: Roxy Peck; Chris Olsen; Jay L. Devore
Publisher: Brooks Cole
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Textbook Question
Chapter 8.2, Problem 14E
The time that a randomly selected individual waits for an elevator in an office building has a uniform distribution over the interval from 0 to 1 minute. For this distribution μ = 0.5 and σ ＝ 0.289.
- a. Let x̄ be the sample
mean waiting time for a random sample of 16 individuals. What are the mean and standard deviation of the sampling distribution of x̄？ - b. Answer Part (a) but for a random sample of 50 individuals.
- c. Draw a picture of the approximate sampling distribution of x̄ when n = 50.
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Suppose that the average salary at a certain
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Chapter 8 Solutions
Introduction to Statistics and Data Analysis
Ch. 8.1 - Explain the difference between a population...Ch. 8.1 - What is the difference between x and ? Between s...Ch. 8.1 - For each of the following statements, identify the...Ch. 8.1 - Consider a population consisting of the following...Ch. 8.1 - Select 10 additional random samples of size 5 from...Ch. 8.1 - Consider the following population: {1, 2, 3, 4}....Ch. 8.1 - Consider the following population: {2, 3, 3, 4,...Ch. 8.2 - A random sample is selected from a population with...Ch. 8.2 - For which of the sample sizes given in the...Ch. 8.2 - Explain the difference between and x and between ...
Ch. 8.2 - Suppose that a random sample of size 64 is to be...Ch. 8.2 - The time that a randomly selected individual waits...Ch. 8.2 - Let x denote the time (in minutes) that it takes a...Ch. 8.2 - In the library on a university campus, there is a...Ch. 8.2 - Suppose that the mean value of interpupillary...Ch. 8.2 - Suppose that a sample of size 100 is to be drawn...Ch. 8.2 - A manufacturing process is designed to produce...Ch. 8.2 - College students with checking accounts typically...Ch. 8.2 - An airplane with room for 100 passengers has a...Ch. 8.2 - The thickness (in millimeters) of the coating...Ch. 8.3 - A random sample is to be selected from a...Ch. 8.3 - a. For which of the sample sizes given in the...Ch. 8.3 - The article "Unmarried Couples More Likely to Be...Ch. 8.3 - Prob. 26ECh. 8.3 - A certain chromosome defect occurs in only 1 in...Ch. 8.3 - Prob. 28ECh. 8.3 - Prob. 29ECh. 8.3 - Suppose that a candidate for public office is...Ch. 8.3 - A manufacturer of computer printers purchases...Ch. 8 - The nicotine content in a single cigarette of a...Ch. 8 - Let x1, x2, , x100 denote the actual weights (in...Ch. 8 - Suppose that 20% of the subscribers of a cable...Ch. 8 - Water permeability of concrete can be measured by...Ch. 8 - Suppose that 40% of all U.S. employees contribute...Ch. 8 - The amount of money spent by a customer at a...
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