Maths Olympiad Prep

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, 2014

Algebra Difficulty 1.1 Junior Find the answer Canada

30% of 200 equals

(A) 0.060.06 (B) 0.60.6 (C) 66 (D) 6060 (E) 600600

A number or a short expression. Fractions can be typed as 3/2, and spacing doesn't matter.

Solution

30% of 200 equals 30100×200=60\frac{30}{100} \times 200 = 60.

Alternatively, we could note that 30% of 100 is 30 and 200=2×100200 = 2\times 100, so 30% of 200 is 30×230 \times 2 which equals 60.

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Source: CEMC, University of Waterloo, licensed CC-BY-NC-4.0. Statement reproduced verbatim; metadata (topic, difficulty) added by this project.