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

Answer:

There are 36 boys in the class.

Step-by-step 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:

$\frac{x}{4} + \frac{y}{2} = 12$

Since $y = 42 - x$

$\frac{x}{4} + \frac{42 - x}{2} = 12$

Multiplying everything by 4.

$x + 84 - 2x = 48$

$-x = -36$

$x = 36$

There are 36 boys in the class.