You can put this solution on YOUR website! Suppose you flip a coin 3 times. What is the probability that exactly 2 of your flips were heads?
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Binomial Problem with n = 3 ; p(head) = 1/2
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P(x = 2) = 3c2(1/2)^2*(1/2) = 3/8
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Cheers,
Stan H.
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