SOLUTION: A student takes an exam containing 16 true or false questions. If a student randomly guesses on the entire exam, what is the expected value of the number of correct answers?

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Question 363712: A student takes an exam containing 16 true or false questions. If a student randomly guesses on the entire exam, what is the expected value of the number of correct answers?
Found 2 solutions by stanbon, robertb:
Answer by stanbon(75887) About Me  (Show Source):
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A student takes an exam containing 16 true or false questions. If a student randomly guesses on the entire exam, what is the expected value of the number of correct answers?
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E(x) = np = 16*1/2 = 8
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Cheers,
Stan H.

Answer by robertb(5830) About Me  (Show Source):
You can put this solution on YOUR website!
This is a binomial experiment with n = 16 and p = 0.5. Thus mu+=+np+=+16%2A0.5+=+8. Therefore he can expect to get 8 correct answers just by guessing.