Browse Questions

# The mean of a set of observation is $\overline x$. If each observation is divided by $a, a \neq 0$ and then is increased by 10, then mean of the new set is

$\begin {array} {1 1} (A)\;\large\frac{\overline x}{a} & \quad (B)\;\large\frac{\overline x+10}{a} \\ (C)\;\large\frac{\overline x+10a}{a} & \quad (D)\;a\overline x+b \end {array}$

Can you answer this question?

If each observation is divided by $a$
then new mean = $\large\frac{\overline x}{a}$
Now, each item is increased by 10
Required mean = $\large\frac{\overline x}{a}$ $+10$
$= \large\frac{\overline x +10a}{a}$
Ans : (C)
answered Jan 26, 2014