# NYU has a ratio of 3 girls to 2 boys in class. If there are 12 boys in class, how many girls are there?

Jan 5, 2017

You can use a proportion to solve this problem.

#### Explanation:

So, from the problem we know 2 things:

• The ratio of girls to boys is 3 to 2.
• Hypothetically, there are 12 boys.

We can use a proportion to solve this problem:

$\frac{3}{2} = \frac{x}{12}$

And then we cross-multiply to get this:

$2 x = 36$

Then, using the Division Property of Equality, we divide by 2 on both sides, resulting in the answer:

$x = 18$