Bundle: Cengage Advantage Books: Essentials of Statistics for the Behavioral Sciences, 8th + LMS Integrated for Aplia, 1 term Printed Access Card
8th Edition
ISBN: 9781305427204
Author: Frederick J Gravetter, Larry B. Wallnau
Publisher: Cengage Learning
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Chapter 6, Problem 20P
A report in 2010 indicates that Americans between the ages of 8 and 18 spend an average of μ = 7.5 hours per day using some sort of electronic device such as smart phones, computers, or tablets. Assume that the distribution of times is normal with a standard deviation of σ = 2.5 hours and find the following values.
- a. What is the
probability of selecting an individual who uses electronic devices more than 12 hours a day? - b. What proportion of 8- to 18-year-old Americans spend between 5 and 10 hours per day using electronic devices? In symbols. p(5 < X < 10) = ?
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Chapter 6 Solutions
Bundle: Cengage Advantage Books: Essentials of Statistics for the Behavioral Sciences, 8th + LMS Integrated for Aplia, 1 term Printed Access Card
Ch. 6.1 - A survey of the students in a psychology class...Ch. 6.1 - A jar contains 10 red marbles and 30 blue marbles....Ch. 6.1 - Suppose that you are going to select a random...Ch. 6.2 - Find the proportion of a normal distribution that...Ch. 6.2 - For a normal distribution, find the z-score...Ch. 6.2 - Prob. 3LCCh. 6.3 - For a normal distribution with a mean of = 60 and...Ch. 6.3 - Scores on the Mathematics section of the SAT...Ch. 6.3 - What is the probability of selecting a score...Ch. 6 - A local hardware store has a Savings Wheel at the...
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