Question

A school has a student population of 560. The number of girls is $14\frac{2}{7}\%$ of the number of boys. How many girls are in the school?

• A. $100$
• B. $70$
• C. $80$
• D. $140$

Answer 1

The correct option is B $70$

Given that the total student population of the school is $560$ and the number of girls is $14\frac{2}{7}\%$ of the number of boys.

Let the total number of boys in the school be $B$.

Hence, number of girls $=14\frac{2}{7}\%\times B=\frac{100}{7}\%\times B$

$\Rightarrow \frac{1}{7}\times B=\frac{B}{7}$

Also, total number of boys + total number of girls = Total students

$\therefore B+\frac{B}{7}=560$

$\Rightarrow \frac{8B}{7}=560$
$\therefore B=560\times \frac{7}{8}=490$

So, number of girls $=560-490=70$

Hence, there are $70$ girls in the school.