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
B
The number of coins that currently show heads is 40% of 150, which is 60. To have the same number of heads showing as tails, John needs 75 coins showing heads. Therefore the number of coins he needs to turn over is 75 − 60 = 15.
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