Maths Olympiad Prep

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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) 22 (B) 44 (C) 55 (D) 66 (E) 77

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