The mean deviation of the variates 40, 62, 68, 76, 54 from their arithmetic mean is
9.4
10
11
10.4
A.M=40+62+68+76+545=3005=60∴M.D.=∑|xi−¯x|n=|40−60|+|62−60|+|68−60|+|76−60|+|54−60|520+2+8+16+65=525=10.4