Midrange, a basic statistical analysis tool, determines the number that is halfway between the highest and lowest number of your data set. To do this, you need to organize your data in order from highest to lowest or lowest to highest. This helps to reduce the chances of choosing the wrong numbers for the midrange formula.
Find the highest and lowest numbers in your data set. For example, suppose you have a data set of 6, 8, 9, 10, 14, 15, 19 and 20. The highest and lowest numbers are 20 and 6.
Add together the highest and lowest number. In the example, 20 plus 6 equals 26.
Divide the sum of the highest and lowest number by two to calculate midrange. In the example, 26 divided by 2 equals a midrange of 13 for the data set.