Median

The median separates the lowest 50% of data values from the highest 50% of data values. To calculate the median, think of it as the "middle" number. The median of the data set {1,2,6} is 2 because 2 is the middle number. However, if there is an even number of data values, we must average the 2 middle numbers. The median of the data set {1,2,6,7} is (2+6)/2=4.