Introduction To Statistics And Data Analysis
6th Edition
ISBN: 9781337793612
Author: PECK, Roxy.
Publisher: Cengage Learning,
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Chapter 8.2, Problem 15E
Let x denote the time (in minutes) that it takes a fifth-grade student to read a certain passage. Suppose that the
- a. If x̄ is the sample mean time for a random sample of n = 9 students, where is the sampling distribution of x̄ centered, and how much does it spread out around the center (as described by its standard deviation)?
- b. Repeat Part (a) for a sample of size of n = 20 and again for a sample of size n = 100. How do the centers and variability of the three x̄ distributions compare to one another?
- c. Which of the
sample sizes in Part (b) would be most likely to result in an x̄ value close to μ, and why?
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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 Younger Adults More Likely than Their...Ch. 8.3 - The article referenced in the previous exercise...Ch. 8.3 - A certain chromosome defect occurs in only 1 in...Ch. 8.3 - The U.S. Census Bureau reported that in 2015, the...Ch. 8.3 - The article Fewer Americans Are Reading, But Dont...Ch. 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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