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

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4.Average

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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

$\frac{m}{n}$

B

$mn$

C

$m-n$

D

$m+n$

Solution

Sum of m numbers $=m n^{2}$, Sum of n number $=n^{2} m^{2}$

Average of $(m+n)=\frac{m n^{2}+n m^{2}}{m+n}=m n$

Standard 13

Quantitative Aptitude

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