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UKMT Junior Kangaroo, 2017

Algebra Difficulty 1.0 Junior Find the answer United Kingdom

Niko counted a total of $60$ birds perching in three trees. Five minutes later, $6$ birds had flown away from the first tree, $8$ birds had flown away from the second tree and $4$ birds had flown away from the third tree. He noticed that there was now the same number of birds in each tree. How many birds were originally perched in the second tree?

(A) $14$ (B) $18$ (C) $20$ (D) $21$ (E) $22$

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