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UKMT Junior Kangaroo, 2023

Number theory Difficulty 1.0 Junior Find the answer United Kingdom

The integer $36$ is divisible by its units digit. The integer $38$ is not. How many integers between $20$ and $30$ are divisible by their units digit?

(A) $2$ (B) $3$ (C) $4$ (D) $5$ (E) $6$

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