
Concept explainers
a.
Obtain the standard deviation of their current ages.
b.
Identify whether the standard deviation of the ages in 20 years will be smaller, larger, or the same as the standard deviation of their current ages or not.
Obtain if the standard deviation of future ages is the same or smaller or larger than the current ages by calculating the standard deviation of future ages.
Identify the effects of standard deviation by adding 20 to each number.
c.
Obtain the mean of the children at their current ages.
d.
Identify whether the mean of the ages in 20 years will be smaller, larger, or the same as the mean of their current ages or not.
Obtain the mean of future ages that are same or smaller or larger than the current ages by calculating the mean of future ages.
Identify the effects of mean by adding 20 to each number.

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Chapter 3 Solutions
Essential Statistics, Books a la Carte Edition Plus MyLab Statistics with Pearson eText - Access Card Package (2nd Edition)
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