The following data give the 1994 total area of farmland (in millions of acres) for 10 states (Statistical Abstract of the United States, 1995). The data, entered in that order, are for the states of Colorado, Iowa, Kansas, Minnesota, Missouri, Nebraska, North Dakota, Oklahoma, South Dakota, and Texas, respectively.
33, 33, 48, 30, 30, 47, 40, 34, 44, 129
(a) Calculate the mean and median for these data.
(b) Do these data contain an outlier? If yes, drop this value and recalculate the mean and median. Which of the two summary measures changes by a large amount when you drop the outlier?
(c) Is the mean or the median a better summary measure for these data? Explain.
(d) Determine the Q1 and Q3 of the above whole data set and determine its interquartile range (IQR).
(e) Draw a Box-and-Whisker plot for these data.