Question 1078246: a multiple choice test has 7 questions each of which has 5 possible answers, only one of which is correct. if judy, who forgot to study for the test guesses on all questions, what is the probability that she will answer exactly 3 questions correctly.
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! a multiple choice test has 7 questions each of which has 5 possible answers, only one of which is correct. if judy, who forgot to study for the test guesses on all questions, what is the probability that she will answer exactly 3 questions correctly.
Binomial Problem with n = 7 and p = 1/5
P(x = 3) = 7C3*(1/5)^3*(4/5)^4 = binompdf(7,1/5,3) = 0.1147
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Cheers,
Stan H.
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