There are $70$ student in class boys, girls ratio $4: 3$, how many are boy and girls?

Given: There are $70$ student in class boys, girls ratio $4: 3$.

To do: To find the number of boys and girls.

Solution:

As given ratio of the boys and girls $=4:3$

Total number of the  students$=70$

Let $4x$ be the number of boys and $3x$ be the number of girls. 

Therefore, Total number of students $=4x+3x=7x$

$\Rightarrow 7x=70$

$\Rightarrow x=\frac{70}{7}$

$\Rightarrow x=10$

Number of the boys$=4x=4\times10=40$

Number of girls$=3x=\times10=30$