16 children are to be divided into two groups A and B of 10 and 6 children. average percent marks ob

English

Gujarati

Hindi

4.Average

medium

$16$ children are to be divided into two groups $A$ and $B$ of $10$ and $6$ children. The average percent marks obtained by the children of group $A$ is $75$ and the average per cent marks of all the $16$ children is $76 .$ What is the average per cent marks of children of group $B$ ?

A

$77 \frac{1}{3}$

B

$78 \frac{1}{3}$

C

$77 \frac{2}{3}$

D

$78 \frac{2}{3}$

Solution

Group $A$ average $=75$

Group $( A + B )$ average $=76$

Required average $=\frac{16 \times 76-10 \times 75}{6}$

$=\frac{760+456-750}{6}=\frac{466}{6}$

$=77 \frac{4}{6}=77 \frac{2}{3} \%$

Standard 13

Quantitative Aptitude

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