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UKMT Pink Kangaroo, 2022

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

The product of the digits of the positive integer $N$ is $20$ . One of the following could not be the product of the digits of $N+1$ . Which is it?

(A) $24$ (B) $25$ (C) $30$ (D) $35$ (E) $40$

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