Question

The ratio of the numbers of boys to girls in a school is 3:5,if there are 900 students in the school. Find the number of boys and girls

Answer 1

$\overline{\underline{\boxed{\sf GIVEN \darr }}}$

• The ratio of the numbers of boys to girls in a school is 4:5,if there are 900 students in the school.

• Find the number of boys and girls.

$\overline{\underline{\boxed{\sf HOW \: TO \: DO \darr}}}$

• First we have to find the sum of ratio by adding 4 and 5 which is the ratio of Boys and Girls. After that we need to divide the ratio by sum of ratio and multiply it with the total no of students, then we can get the no of girls, subtracting no of boys from total no of students and then at last we will verify them by adding the number of boys and girls which should be equal to the total no of students in the school.

$\overline{\underline{\boxed{\sf SOLUTION \darr }}}$

Total no of students in the school = 900

As per the instructions we will first find the sum of ratio of boys and girls

✏ Ratio of boys = 4

✏ Ratio of girls = 5

Now,

• Sum of ratio = 4 + 5 → 9

The next and the last step is to find the number of boys and girls

$\leadsto \frak{ {\sf N}umber \: of \: bo {\sf y}s } \frak{ = \frac{ratio \: of \: boys}{su m\:of \: ratio} \times 900 }$

$\leadsto \frak{ \frac{3}{ \cancel9} \times \cancel{ 900} }$

$\frak{ \therefore \: total \: no \: of \: boys \: in \: the \: school \: is \: 300}$

Now to find the number of girls

No of girls = Total no of students - No of Boys

No of girls = 900 - 300

No of girls = 600

So there are 600 girls in the school

$\overline{\underline{\boxed{\sf VERIFICATION \darr }}}$

Total no of students = No of girls + No of boys

900 = 600 + 300

900 = 900

HENCE, VERIFIED !!