CEMC Pascal, 2004

Number theory Difficulty 1.0 Junior Find the answer Canada

The fractions $\frac{1}{9}$ , $\frac{1}{4}$ and $\frac{1}{18}$ are to be added. What is their lowest common denominator?

(A) $648$ (B) $162$ (C) $72$ (D) $36$ (E) $18$

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