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UKMT Intermediate Mathematical Challenge, 2025

Number theory Difficulty 1.0 Junior Find the answer United Kingdom

Owen chooses a positive integer $n$ so that $3n + 7$ is an even integer. Which of these is an odd integer?

(A) $n - 1$ (B) $n + 3$ (C) $3n + 2$ (D) $4n$ (E) $5n + 3$

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