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UKMT Junior Mathematical Challenge, 2022

Combinatorics Difficulty 2.0 Junior Find the answer United Kingdom

A group of children stand evenly spaced around a circular ring and are numbered consecutively 1, 2, 3, and so on. Number 13 is directly opposite number 35. How many children are there in the ring?

(A) $42$ (B) $44$ (C) $46$ (D) $48$ (E) $50$

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