Question 552197: There are 5 multiple choice questions on an exam. Each with four possible answers. Find the following probabilities.
A exactly 3 are correct
B at least 2 are correct
C all five are correct
D no more than 4 are correct
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! There are 5 multiple choice questions on an exam. Each with four possible answers. Find the following probabilities.
Binomial Problem with n = 5 and p(correct) = 1/4
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A exactly 3 are correct
P(x = 3) = 5C3*(1/4)^3*(3/4)^2 = 0.0879
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B at least 2 are correct
P(2 <= x <= 5) = 1 - binomcdf(5,1/4,1) = 0.3672
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C all five are correct
P(x = 5) = (1/4)^5 = 0.0009766
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D no more than 4 are correct
P(0 <= x <= 4) = binomcdf(5,1/4,4) = 0.9990
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Cheers,
Stan H.
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