Question

Please solve this question i have got exam next week?

Answer 1

The ratio of boys: girls is 4:5

It means that if there are `9` students (`4+5` which is the addition of ratios), then `4` are boys.

or `4` out of `9` students are boys.

It can be written as = `4/9` boys.

Now, it given that number of boys = `220`

and we know that this `220` boys are `4/9` of the total students

Let the Total students attending the school = `x`

So, `4/9xxx` = `220`

or `4x` = `220xx9` = `1980`

or `x` = `1980/4` = `495` students

Answer 2

`495` students

Explanation:

If the ratio of boys to girls is `4" ":" "5`, then we know the following:

There are more girls than boys.

For every `4` boys there are `5` girls

The total number of students is a multiple of `9`.

We could also state the question as:

Increase `220` in the ratio `9" ":" "4`

This will give us the total number of students in one calculation.

`220 xx 9/4`

`=495` students

Note that dividing: `220 div4 = 55` tells us how many students one part represents.

So to find `9` parts: `55 xx9 = 495`