Chapter 6.B, Problem 19E

Understanding Variation. The following exercises give four data sets consisting of seven numbers.

a. Make a histogram for each set.

b. Give the five-number summary and draw a boxplot for each set.

c. Compute the standard deviation for each set.

d. Based on your results, briefly explain how the standard deviation provides a useful single-number summary of the variation these data sets.

19. The following sets of numbers all have a mean of 9:

{9, 9, 9, 9, 9, 9, 9}, {8, 8, 9, 9, 9, 10, 10},

{8, 8, 8, 9, 10, 10, 10}, {6, 6, 6, 9, 12, 12, 12}