Answer :
1. Find the mean of the data: (-7 -2 + 1 + 4)/4 = -1
2. Find the absolute value of differences between each data an the mean:
1) |-7 -(-1)| = |-7 + 1| = |-6| = 6
2) |-2-(-1)| = |-2+1| = |-1| = 1
3) |1 -(-1)| = |1+1| = |2| = 2
4) |4 -(-1)| = |4+1|=|5|=5
3) Calculate the mean of those differences:
( 6 + 1 + 2 + 5) / 4 = 14/4 = 3.5
2. Find the absolute value of differences between each data an the mean:
1) |-7 -(-1)| = |-7 + 1| = |-6| = 6
2) |-2-(-1)| = |-2+1| = |-1| = 1
3) |1 -(-1)| = |1+1| = |2| = 2
4) |4 -(-1)| = |4+1|=|5|=5
3) Calculate the mean of those differences:
( 6 + 1 + 2 + 5) / 4 = 14/4 = 3.5