Question

7. There are 42 pupils in a class. 12 of them are Malays while the rest are

Chinese. 1/4 of the boys and 12 of the girls are Malay. How many boys
are there in the class?



I NEED THIS ASAP!!!

Answer 1

There are 36 boys in the class.

Explanation:

This question is solved by a system of equations.

I am going to say that:

x is the number of boys

y is the number of girls.

There are 42 pupils in a class.

This means that
`x + y = 42`.

Since we want x, we have that
`y = 42 - x`

12 of them are Malays while the rest are Chinese. 1/4 of the boys and 1/2 of the girls are Malay.

This means that:

`(x)/(4) + (y)/(2) = 12`

Since
`y = 42 - x`

`(x)/(4) + (42 - x)/(2) = 12`

Multiplying everything by 4.

`x + 84 - 2x = 48`

`-x = -36`

`x = 36`

There are 36 boys in the class.