SOLUTION: An exam consists of 20 true-or-false questions. If a student guesses at every answer, what is the probability that he or she will answer exactly 12 questions correctly? (Round your
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Question 528339: An exam consists of 20 true-or-false questions. If a student guesses at every answer, what is the probability that he or she will answer exactly 12 questions correctly? (Round your answer to three decimal places.) Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! An exam consists of 20 true-or-false questions. If a student guesses at every answer, what is the probability that he or she will answer exactly 12 questions correctly?
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Binomial Problem with n = 20 and p(correct) = 1/2
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P(x = 12) = 20C12*(1/2)^12*(1/2)^8 = 0.1201
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Cheers,
Stan H.
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