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

The positive integers aa, bb, cc, dd satisfy the equation ab=2cdab = 2cd. Which of the following numbers could not be the value of the product abcdabcd?

(A) 5050 (B) 100100 (C) 200200 (D) 450450 (E) 800800

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