1989 AMC 8 Problem 9

Attempt Problem 9 of the 1989 AMC 8 below, then check your answer against the professionally curated solution from LIVE by Po-Shen Loh. You can also try the full timed exam, view all 1989 AMC 8 solutions, or check the answer key.

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There are $2$ boys for every $3$ girls in Ms. Johnson's math class. If there are $30$ students in her class, what percent of them are boys?

$12\%$

$20\%$

$40\%$

$60\%$

$66\dfrac{2}{3}\%$

Difficulty rating: 660

Boys make up $2$ out of every $2 + 3 = 5$ students, which is $\frac{2}{5}$ of the class. The total of $30$ students is not even needed.

As a percent, $\frac{2}{5} = 40\%.$

Thus, the correct answer is C .