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UKMT Intermediate Mathematical Challenge, 2012

Number theory Difficulty 2.0 Junior Find the answer United Kingdom

An 'abundant' number is a positive integer $N$ , such that the sum of the factors of $N$ (excluding $N$ itself) is greater than $N$ . What is the smallest abundant number?

(A) $5$ (B) $6$ (C) $10$ (D) $12$ (E) $15$

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