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UKMT Junior Mathematical Challenge, 2026

Combinatorics Difficulty 2.0 Junior Find the answer United Kingdom

Carl counts in a curious way! He starts at $1$ , but then always misses out multiples of three and multiples of five. What number would Carl say last when he counts $15$ items?

(A) $22$ (B) $23$ (C) $26$ (D) $28$ (E) $29$

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