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CEMC Gauss (Grade 7), 2009

Number theory Difficulty 2.0 Junior Find the answer Canada

If $x, y$ and $z$ are positive integers with $xy = 18$ , $xz = 3$ and $yz = 6$ , what is the value of $x + y + z$ ?

(A) $6$ (B) $10$ (C) $25$ (D) $11$ (E) $8$

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