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1985 AJHSME Problems/Problem 16

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Problem

The ratio of boys to girls in Mr. Brown's math class is 2:3. If there are 30 students in the class, how many more girls than boys are in the class?

\text{(A)}\ 1 \qquad \text{(B)}\ 3 \qquad \text{(C)}\ 5 \qquad \text{(D)}\ 6 \qquad \text{(E)}\ 10

Solution

Let the number of boys be 2x. It follows that the number of girls is 3x. These two values add up to 30 students, so 2x+3x=5x=30\Rightarrow x=6

The difference between the number of girls and the number of boys is 3x-2x=x, which is 6, so the answer is \boxed{\text{D}}.

See Also

1985 AJHSME (ProblemsResources)
Preceded by
Problem 15
Followed by
Problem 17
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