SOLUTION: 25% of all students find this BS exam difficult. You select four random students. What is the probability that exactly two of them find this exam difficult?

Question 1132662: 25% of all students find this BS exam difficult. You select four random students. What is the probability that exactly two of them find this exam difficult?
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
25% of all students find this BS exam difficult. You select four random students. What is the probability that exactly two of them find this exam difficult?
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P(x = 2) = 4C2*0.25^2*0.75^2 = binompdf(4,0.25,2) = 0.2109
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Cheers,
Stan H.
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