12th Edition

ISBN: 9781337630580

Author: Dale Ewen

Publisher: Cengage Learning

Concept explainers

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…

Mean, Median, Mode

It is a descriptive summary of a data set. It can be defined by using some of the measures. The central tendencies do not provide information regarding individual data from the dataset. However, they give a summary of the data set. The central tendency o…

Z-Scores

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 15.8, Problem 2E

Make a frequency distribution of the following scores from a mathematics test and use it to find the mean score.

85, 73, 74, 69, 87, 81, 68, 76, 78, 75, 88, 85, 67, 83, 82, 95, 63, 84, 94, 66, 84, 78, 96, 67, 63, 59, 100, 90, 100, 94, 79, 79, 74

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Chapter 15.8, Problem 1E

Chapter 15.8, Problem 3E

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Chapter 15 Solutions

Elementary Technical Mathematics

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Make a frequency distribution of the following scores from a mathematics test and use it to find the mean score. 85, 73, 74, 69, 87, 81, 68, 76, 78, 75, 88, 85, 67, 83, 82, 95, 63, 84, 94, 66, 84, 78, 96, 67, 63, 59, 100, 90, 100, 94, 79, 79, 74

Solution Summary: The author calculates the frequency distribution of the following scores from a mathematics test and uses it to find the mean score.

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Chapter 15 Solutions