Most of the problems in this and other chapters deal with “real” data for which computations are most efficiently performedwith computers. Since a little experience in manual computing is healthy, here are 15 observations of a variable having no particular meaning:

12 18 22 17 20 15 19 13 23 8 14 14 19 11 30.

(a) Compute the mean, median, variance, range, and interquartile range for these observations.

b) Produce a stem and leaf plot.

(c) Write a brief description of this data set.