Introduction to Probability and Statistics
14th Edition
ISBN: 9781133103752
Author: Mendenhall, William
Publisher: Cengage Learning
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Chapter 7.5, Problem 7.26E
Faculty Salaries Suppose that college faculty with the rank of prolessor at public 2-year institutions earn an average of $71,802 per year7 with a standard deviation of $4000. In an attempt to verify this salary level, a random sample of 60 professors was selected from a personnel database for all 2—year institutions in the United States.
- Describe the sampling distribution of the sample mean
- Within what limits would you expect the sample average to lie, with
probability .95? - Calculate the probability that the sample mean
- If your random sample actually produced a sample mean of $73,000, would you consider this unusual? What conclusion might you draw?
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Chapter 7 Solutions
Introduction to Probability and Statistics
Ch. 7.2 - A population consists of N=500 experimental units....Ch. 7.2 - A political analyst wishes to select a sample of...Ch. 7.2 - Prob. 7.3ECh. 7.2 - Prob. 7.4ECh. 7.2 - Prob. 7.9ECh. 7.2 - Prob. 7.11ECh. 7.2 - Ask America A 2003 nationwide policy surv ey...Ch. 7.5 - Random samples of size n were selected from...Ch. 7.5 - Prob. 7.16ECh. 7.5 - A population consists of N=5 numbers: 1, 3, 5, 6,...
Ch. 7.5 - Prob. 7.18ECh. 7.5 - A random sample of n observations is selected from...Ch. 7.5 - Prob. 7.20ECh. 7.5 - Prob. 7.21ECh. 7.5 - Prob. 7.22ECh. 7.5 - Prob. 7.23ECh. 7.5 - Prob. 7.24ECh. 7.5 - Suppose a random sample of n=25 observal ions is...Ch. 7.5 - Faculty Salaries Suppose that college faculty with...Ch. 7.5 - Potassium Levels The normal daily human potassium...Ch. 7.5 - Prob. 7.32ECh. 7.5 - Normal Temperatures In Exercise 1.67, Allen...Ch. 7.5 - Prob. 7.34ECh. 7.6 - Prob. 7.35ECh. 7.6 - Prob. 7.36ECh. 7.6 - Prob. 7.37ECh. 7.6 - Randome samples of size n=500 were selected from a...Ch. 7.6 - Prob. 7.39ECh. 7.6 - Prob. 7.40ECh. 7.6 - Prob. 7.41ECh. 7.6 - Prob. 7.42ECh. 7.6 - Prob. 7.43ECh. 7.7 - Prob. 7.48ECh. 7.7 - Prob. 7.49ECh. 7.7 - Prob. 7.50ECh. 7.7 - Prob. 7.51ECh. 7.7 - Prob. 7.52ECh. 7.7 - Prob. 7.54ECh. 7.7 - Prob. 7.56ECh. 7.7 - Prob. 7.57ECh. 7.7 - Prob. 7.59ECh. 7 - Refer to Exercise 7.60. Find the sampling...Ch. 7 - Prob. 7.63SECh. 7 - Prob. 7.66SECh. 7 - What survey design is used in each of these...Ch. 7 - Prob. 7.74SECh. 7 - Prob. 7.76SECh. 7 - Prob. 7.78SECh. 7 - Prob. 7.79SECh. 7 - Prob. 7.80SECh. 7 - Prob. 7.81SECh. 7 - Prob. 7.82SECh. 7 - Prob. 7.84SECh. 7 - Prob. 7.85SE
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