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UKMT Junior Mathematical Challenge, 2021

Combinatorics Difficulty 2.0 Junior Find the answer United Kingdom

Some fish, some dogs and some children are swimming in a bay. There are 40 legs in total, twice as many heads as tails and more dogs than fish. How many fish are in the bay?

(A) $1$ (B) $2$ (C) $3$ (D) $4$ (E) $5$

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