### If the average of m numbers is n^{2} and that of n numbers is m^{2} , then the average of (m + n) numbers is.

**A.** m – n

**B.** mn

**C.** m + n

**D.** $\frac{\boldsymbol{m}}{\boldsymbol{n}}$

## Show Answer

###
Answer-B

Solution-

__Solution(By Apex Team)__

$\begin{array}{l}\text{Sum of m numbers = mn}^2\\
\text{Sum of n numbers = nm}^2\\
\text{∴ Average of (m + n) numbers}\\
\begin{array}{l}=\Large\frac{mn(m+n)}{(m+n)}\\
=\mathrm{mn}\end{array}\end{array}$