SOLUTION: 10 questions test. you know the answer to 5 questions of true or false. You quess on the last 5. What is the probability that you will have at least eight c

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Question 256326:










10 questions test. you know the answer to 5 questions of true or false. You quess on the last 5. What is the probability that you will have at least eight correct answers. Express your answer as a common fraction. Hint look at the word (least) and think about combinations nCr.








Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
10 questions test. you know the answer to 5 questions of true or false. You quess on the last 5. What is the probability that you will have at least eight correct answers. Express your answer as a common fraction. Hint look at the word (least) and think about combinations nCr.
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You need at least 3 correct from the 5.
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P(at least 3 of 5) = 1 - binomcdf(5,1/2,2)
= 1 - 0.5
= 0.5
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Cheers,
Stan H.