Question

what is the mean absolute deviation of the data: 15.6, 19.8, 12.2, 21.7, 25.3, 16.5 and 19.8? Round to the nearest tenth.

Answer 1

Mean Deviation = 15.6 + 19.8 + 12.2 + 21.7 +25.3 + 16.5 + 19.8 / 7
Mean Deviation = 18.70

Answer 2

mean absolute deviation = ∑|(xₐ - mean )| ÷ n

where xₐ  is every term in the data set

n is total number of terms

mean for the given data set = sum of all terms ÷ total number of terms =

130.9 ÷ 7 = 18.7

mean absolute deviation = ∑|(xₐ - mean )| ÷ n

mean absolute deviation == 23.6 ÷ 7 = 3.37