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UKMT Junior Kangaroo, 2018

Combinatorics Difficulty 2.0 Junior Find the answer United Kingdom

A large circular table has $60$ chairs around it. What is the largest number of people who can sit around the table so that each person is only sitting next to exactly one other person?

(A) $40$ (B) $36$ (C) $30$ (D) $25$ (E) $20$

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