Difference between revisions of "2005 AMC 12B Problems/Problem 1"

(Problem)
(Solution)
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== Solution ==
 
== Solution ==
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<math>2=0.1x \Rightarrow x=20</math>.
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<math>2=0.2y \Rightarrow y=10</math>.
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<math>\therefore x-y=20-10=\boxed{10}</math>.
  
 
== See also ==
 
== See also ==
 
* [[2005 AMC 12B Problems]]
 
* [[2005 AMC 12B Problems]]

Revision as of 21:26, 17 April 2009

Problem

Two is $10\%$ of $x$ and $20\%$ of $y$. What is $x-y$?

$\mathrm{(A)}\ 1      \qquad \mathrm{(B)}\ 2      \qquad \mathrm{(C)}\ 5      \qquad \mathrm{(D)}\ 10      \qquad \mathrm{(E)}\ 20$

Solution

$2=0.1x \Rightarrow x=20$.

$2=0.2y \Rightarrow y=10$.

$\therefore x-y=20-10=\boxed{10}$.

See also

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