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UKMT Pink Kangaroo, 2020

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

The positive integers $a$ , $b$ , $c$ , $d$ satisfy the equation $ab = 2cd$ . Which of the following numbers could not be the value of the product $abcd$ ?

(A) $50$ (B) $100$ (C) $200$ (D) $450$ (E) $800$

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