Question

The mean deviation of the data $2$, $9$, $9$, $3$, $6$, $9$, $4$ from the mean is

• A. $2.23$
• B. $2.57$
• C. $3.23$
• D. $3.57$

Answer 1

Answer: (B)

Mean $\bar{x}=\frac{2+9+9+3+6+9+4}{7}$
$=\frac{42}{7}=6$
$M.D.\left(\bar{x}\right)=\frac{\Sigma |x_i-\bar{x}|}{n}$
$=\frac{4+3+3+3+0+3+2}{7}=2.57$