An outlier of a set of data is a data value that is too small or too large compared to other values in the set of data. Range of a set of data is the difference between the largest data value and the smallest data valu in the set of data. Range of 23, 23, 25, 27, 34, 34, 35, 41, 45, 45, 78 is 78 - 23 = 55 When the outlier 78 is removed, the range of the data set 23, 23, 25, 27, 34, 34, 35, 41, 45, 45 is 45 - 23 = 22 Thus, when the outlier 78 is removed, the range of the data set decreases by 55 - 22 = 33. Therefore, the correct answer to the question "The outlier, 78, is removed from the data set shown. 23, 23, 25, 27, 34, 34, 35, 41, 45, 45, 78 How does this affect the range?" is "The range is decreased by 33." (option D).