5th Edition

ISBN: 9781034509998

Author: Sullivan

Publisher: PEARSON

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Probability distributions are of two types, which are continuous probability distributions and discrete probability distributions. A continuous probability distribution contains an infinite number of values. For example, if time is infinite: you could co…

Normal Distribution

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Textbook Question

Chapter 7.2, Problem 31AYU

In Problems 23–32, assume that the random variable X is normally distributed, with mean μ = 50 and standard deviation σ = 7. Compute the following probabilities. Be sure to draw a normal curve with the area corresponding to the probability shaded.

31. P(38 < X ≤ 55)

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 7.2, Problem 30AYU

Chapter 7.2, Problem 32AYU

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Chapter 7 Solutions

>LCPO< FUND OF STATISTICS

Ch. 7.1 - A _____ _____ _____ is an equation used to compute...Ch. 7.1 - A _______ is an equation, table, or graph used to...Ch. 7.1 - True or False: The normal curve is symmetric about...Ch. 7.1 - The area under the normal curve to the right of ...Ch. 7.1 - The points at x = _____ and x = _____ are the...Ch. 7.1 - The area under a normal curve can be interpreted...Ch. 7.1 - For Problems 712, determine whether the graph can...Ch. 7.1 - For Problems 712, determine whether the graph can...Ch. 7.1 - For Problems 712, determine whether the graph can...Ch. 7.1 - Prob. 10AYU

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In Problems 23–32, assume that the random variable X is normally distributed , with mean μ = 50 and standard deviation σ = 7. Compute the following probabilities. Be sure to draw a normal curve with the area corresponding to the probability shaded . 31. P (38 &lt; X ≤ 55)

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Chapter 7 Solutions

In Problems 23–32, assume that the random variable X is normally distributed , with mean μ = 50 and standard deviation σ = 7. Compute the following probabilities. Be sure to draw a normal curve with the area corresponding to the probability shaded . 31. P (38 < X ≤ 55)