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UKMT Junior Kangaroo, 2023

Combinatorics Difficulty 3.0 AMC 10/12 Find the answer United Kingdom

A group of $40$ boys and $28$ girls stand hand in hand in a circle facing inwards. Exactly $18$ of the boys give their right hand to a girl. How many boys give their left hand to a girl?

(A) $12$ (B) $14$ (C) $18$ (D) $20$ (E) $22$

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