UKMT Grey Kangaroo, 2023

Algebra Difficulty 2.0 Junior Find the answer United Kingdom

John has 150 coins. When he throws them on the table, 40% of them show heads and 60% of them show tails. How many coins showing tails does he need to turn over to have the same number showing heads as showing tails?

(A) $10$ (B) $15$ (C) $20$ (D) $25$ (E) $30$

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