CEMC Pascal, 2008

Algebra Difficulty 1.0 Junior Find the answer Canada

At Mathville Junior High School, 30 boys and 20 girls wrote the Pascal Contest. Certificates were awarded to 30% of the boys and 40% of the girls. What percentage of all of the participating students received certificates?

(A) $34$ (B) $35$ (C) $36$ (D) $17$ (E) $70$

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