Question

The mean of $12$ numbers is $48$. If each numbers is multiplied by $4$ what will be the new mean?

Answer 1

Let $x_1,x_2,....,x_{12}$ be $12$ numbers.

Mean $=\frac{x_1+x_2+....+x_{12}}{12}=48$

$\therefore x_1+x_2+....+x_{12}=48\times 12$

New mean $=\frac{4x_1+{4x}_2+....+{4x}_{12}}{12}$

$=\frac{4(x_1+x_2+....+x_{12})}{12}$

$=4\times 48=192$

New Mean $=192$