Twenty-Eight Applicants Interested in Working for the Food Stamp Program

Short Answer

Twenty-eight applicants interested in working for the Food Stamp program took an examination designed to measure their aptitude for social work. A stem-and-leaf plot of the 28 scores appears below, where the first column is the count per "branch," the second column is the stem value, and the remaining digits are the leaves.
a. Should the Empirical Rule be applied to this data set?
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b. Use the range approximation to determine an approximate value for the standard deviation.
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Is this a good approximation?
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