Competition problem — Algebra — Maths Olympiad Prep

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Algebra Difficulty 1.9 Junior Find the answer

Two is $10 \%$ of $x$ and $20 \%$ of $y$ . What is $x - y$ ?
$(\mathrm {A}) \ 1$ $(\mathrm {B}) \ 2$ $(\mathrm {C})\ 5$ $(\mathrm {D}) \ 10$ $(\mathrm {E})\ 20$

Your answer

Multiple choice: answer with the letter of the option you want.

Solution

$2 = \frac {1}{10}x \Longrightarrow x = 20,$ $2 = \frac{1}{5}y \Longrightarrow y = 10,$ $x-y = 20 - 10=10 \mathrm{(D)}$ .

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Source: NuminaMath-1.5, licensed Apache-2.0. Statement and solution reproduced as published; topic and difficulty added by this site.