UKMT Pink Kangaroo, 2015

Combinatorics Difficulty 2.0 Junior Find the answer United Kingdom

Three inhabitants of the planet Zog met in a crater and counted each other's ears. Imi said, "I can see exactly 8 ears"; Dimi said, "I can see exactly 7 ears"; Timi said, "I can see exactly 5 ears". None of them could see their own ears. How many ears does Timi have?

(A) $2$ (B) $4$ (C) $5$ (D) $6$ (E) $7$

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