John tossed a fair coin 2 times. What is the probability that the coin landed heads up exactly twice? Pick:
A) 0.5 B) 0.55 C) 0.6 D) 0.65 E) 0.7
The probability is exactly same as the cion landed tail up once. That is 2*(1/2)^2 = 2/4 =0.5.   The answer is, therefore, (0.5).
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John tossed a fair coin 2 times. What is the probability that the coin landed heads up exactly twice?