 # Mean, Median, Mode and Range

The mean, median, mode, and range are all values that can be helpful when analyzing data. Mathematicians and statisticians use these numbers to draw conclusions about a specific sample size. Going beyond the classroom, mean, median, mode, and range are used in a variety of career fields and jobs, such as IT professionals, management, data clerks, insurance analysts, actuaries, etc.

Let’s use the following set of numbers to determine the mean, median, mode, and range:

13, 19, 16, 2, 7, 11, 19, 20, 1

The mean is the average of the numbers in a set. To find the mean, divide the sum of the terms by the number of terms in the set.

Example: (13 + 19 + 16 + 2 + 7 + 11 + 19 + 20 + 1) / 9 = 108 / 9 = 12, so the mean (or average) is 12.

The median is the middle number of a set when ordered from least to greatest. If the set contains an odd number of terms, it is rather easy to find the median. Simply cross off a number from the beginning and end until you reach the middle number of the set. When the set contains an even number of terms, to find the median, add the two middle numbers together and then divide by 2 (the number of terms).

Example: 1, 2, 7, 11, 13, 16, 19, 19, 20, so the median is 13.

The mode is the number that appears the most in a set of numbers.

Example: The only number that appears more than once is 19, so the mode is 19.

The range is the difference between the highest value and the lowest value of a set of numbers.

Example: The highest value is 20 and the lowest value is 1, so 20 – 1 = 19. The range of the set is 19.