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Chapter 2: Q.68 (page 134)

Weights aren’t Normal The heights of people of the same gender and similar ages follow Normal distributions reasonably closely. Weights, on the other hand, are not Normally distributed. The weights of women aged 20 to 29 have mean 141.7 pounds and median 133.2 pounds. The first and third quartiles are 118.3 pounds and 157.3 pounds. What can you say about the shape of the weight distribution? Why?

Short Answer

Expert verified

The distribution is right-skewed.

Step by step solution

01

Given Information

The weights of women aged=20to29

Mean=141.7pounds

Median=133.2pounds

The first and third quartiles=118.3pounds

The third quartiles=157.3pounds

02

Explanation

Here are the steps to find the distribution of weights:

  • Due to the unequal mean and median, the shape of the weight distribution is skewed.
  • A right-skewed distribution is also evident since the mean is greater than the median and large values influence the mean.

In other words, the distribution of income is right-skewed.

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