Step 1 :
Find the mean of the data :
(2+4+6+8) / 4 = 20/4 = 5
Step 2 :
Find the distance between each data and mean.
Distance between 2 and 5 is 3
Distance between 4 and 5 is 1
Distance between 6 and 5 is 1
Distance between 8 and 5 is 3
Step 3 :
Add all the distances :
3+1+1+3 = 8
Step 4 :
Divide it by the number of data :
8 / 4 = 2
2 is the average absolute deviation.
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