<PRE><B>Question 820166</B>
A manufacturer of headache medicine claims it is 80 percent effective within a few minutes. That is, out of every 100 users 80 get relief within a few minutes. A group of 12 patients are given the medicine. If the claim is true, what is the probability that 8 have relief within a few minutes?
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Binomial Problem with n = 12 and p(relief) = 0.8
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P(x = 8) = 12C8(0.8)^8(0.2)^4 
= 495*0.1678*0.0016 
= binompdf(12,0.8,8)
= 0.1329
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Cheers,
Stan H.
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