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2003 AMC 12B Problems/Problem 8

Revision as of 22:32, 19 December 2012 by Mathematician153 (talk | contribs)

Let $a$ and $b$ be the digits of $x$,

\[\clubsuit(\clubsuit(x)) = a + b = 3\]

Clearly $\\clubsuit(x)$ can only be $3, 12, 21,$ or $30$ and only $3$ and $30$ are possible to have two digits sum to.

If $\\clubsuit(x)$ is \Rightarrow \text (E)$

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