12th Edition

ISBN: 9780321836960

Author: Mario F. Triola

Publisher: PEARSON

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Chapter 8.4, Problem 31BB

Hypothesis Tests with Known σ. In Exercises 29-32, conduct the hypothesis test using a known value of the population standard deviation σ.

31. Repeat Exercise 11 assuming that the population standard deviation σ is known to be 11.1 years.

11. Oscar-Winning Actresses Data Set 11 in Appendix B lists ages of actresses when they won Oscars, and the summary statistics are n = 82, x ¯ = 35.9 years, and s = 11.1 years. Use a 0.01 significance level to test the claim that the mean age of actresses when they win Oscars is 33 years.

Features Features Normal distribution is characterized by two parameters, mean (µ) and standard deviation (σ). When graphed, the mean represents the center of the bell curve and the graph is perfectly symmetric about the center. The mean, median, and mode are all equal for a normal distribution. The standard deviation measures the data's spread from the center. The higher the standard deviation, the more the data is spread out and the flatter the bell curve looks. Variance is another commonly used measure of the spread of the distribution and is equal to the square of the standard deviation.

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Chapter 8.4, Problem 30BB

Chapter 8.4, Problem 32BB

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Chapter 8 Solutions

Elementary Statistics

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Solution Summary: The author explains the null hypothesis and alternative hypothesis, stating that there is no sufficient evidence to reject the claim that the mean age of actresses when they won Oscars is equal to 33 years.

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