Question

Find a. the mean b. the deviation from the mean for each data item: and c. the sum of the deviations in part b. 146, 153, 155, 160, 161

Answer 1

a. The mean of the data set is:

(146 + 153 + 155 + 160 + 161) / 5 = 155

b. The deviation from the mean for each data item is:

146 - 155 = -9

153 - 155 = -2

155 - 155 = 0

160 - 155 = 5

161 - 155 = 6

c. The sum of the deviations from the mean is:

-9 + (-2) + 0 + 5 + 6 = 0

Note that the sum of the deviations from the mean is always zero, since the positive deviations cancel out the negative deviations.