Question

What is the mean absolute deviation of 25,24,25,23,20,18

Answer 1

The mean absolute deviation is the mean of the absolute values of the differences of the numbers from their mean. It is convenient to let a spreadsheet or calculator do the tedious math. Here it is by hand:

Total of given values: 135

Mean of given values: 135/6 = 22.5

Deviations of given values from the mean:

... {2.5, 1.5, 2.5, 0.5, -2.5, -4.5}

Absolute values of deviations from the mean:

... {2.5, 1.5, 2.5, 0.5, 2.5, 4.5}

Total of those: 14

Mean absolute deviation: 14/6 = 2 1/3.