Question

The mean deviation of the data $3,5,11,13,17,19,23,29$ about its arithmetic mean is

• A. 8.5
• B. 8
• C. 7.2
• D. 7

Answer 1

Answer: (D)

(We have,
$\bar{X}=\frac{3+5+11+13+17+19+23+29}{8}=15$
$\therefore$ Mean deviation about the mean
$\frac{|3-15|+|5-15|+|11-15|+|13-15|+|17-15|+|19-15|+|23-15|+|29-15|}{8}$
$=\frac{12+10+4+2+2+4+8+14}{8}=\frac{56}{8}=7$