Essentials of Statistics for the Behavioral Sciences

8th Edition

ISBN: 9781133956570

Author: Frederick J Gravetter, Larry B. Wallnau

Publisher: Cengage Learning

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The method used for finding the corresponding z-critical value in a normal distribution using the known probability is said to be an inverse normal distribution. The inverse normal distribution is a continuous probability distribution with a family of tw…

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A z-score is a unit of measurement used in statistics to describe the position of a raw score in terms of its distance from the mean, measured with reference to standard deviation from the mean. Z-scores are useful in statistics because they allow compar…

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Textbook Question

Chapter 6.3, Problem 2LC

Scores on the Mathematics section of the SAT Reasoning Test form a normal distribution with a mean of μ = 500 and a standard deviation of σ = 100.

a. If the state college only accepts students who score in the lop 60% on this test, what is the minimum score needed for admission?
b. What is the minimum score necessary to be in the lop 10% of the distribution?
c. What scores form the boundaries for the middle 50% of the distribution?

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 6.3, Problem 1LC

Chapter 6.3, Problem 3LC

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Chapter 6 Solutions

Essentials of Statistics for the Behavioral Sciences

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. 3LC Ch. 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...

Ch. 6 - A psychology class consists of 14 males and 36...Ch. 6 - What are the two requirements for a random sample?Ch. 6 - Draw a vertical line through a normal distribution...Ch. 6 - Draw a vertical line through a normal distribution...Ch. 6 - Find each of the following probabilities for a...Ch. 6 - What proportion of a normal distribution is...Ch. 6 - Find each of the following probabilities for a...Ch. 6 - Find the z-score location of a vertical line that...Ch. 6 - Find the z-score boundaries that separate a normal...Ch. 6 - A normal distribution has a mean of = 70 and a...Ch. 6 - A normal distribution has a mean of = 30 and a...Ch. 6 - For a normal distribution with a mean of = 60 and...Ch. 6 - IQ test scores are standardized to produce a...Ch. 6 - The distribution of SAT scores in normal with =...Ch. 6 - According to a recent, people smile an average of ...Ch. 6 - A recent newspaper article reported the results of...Ch. 6 - Information from the Department of Motor Vehicles...Ch. 6 - A consumer survey indicates that the average...Ch. 6 - A report in 2010 indicates that Americans between...Ch. 6 - Rochester. New York, averages = 21.9 inches of...

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Solution Summary: The author explains that the minimum score needed for admission is 475. The formula for z score is cP(X>x)=0.60

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Chapter 6 Solutions