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UKMT Grey Kangaroo, 2016

Number theory Difficulty 3.0 AMC 10/12 Find the answer United Kingdom

Several different positive integers are written on a blackboard. The product of the smallest two of them is $16$ . The product of the largest two of them is $225$ . What is the sum of all the integers written on the blackboard?

(A) $38$ (B) $42$ (C) $44$ (D) $58$ (E) $243$

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