SOLUTION: If the probability for passing a test (p) is 85% and variance is 0,638, what is the chance that 3 students in a group will not pass the test?

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Question 1047260: If the probability for passing a test (p) is 85% and variance is 0,638, what is the chance that 3 students in a group will not pass the test?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
If the probability for passing a test (p) is 85% and variance is 0.638, what is the chance that 3 students in a group will not pass the test?
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Variance = p*q*n
0.638 = 0.85*0.15*n
n = 5
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P(x = 3) = 5C3*0.15^3*0.85^2 = binompdf(5,0.15,3) = 0.0244
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Cheers,
Stan H.
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