SOLUTION: 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 patien

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Question 820166: 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?

I TRUELY DO NOT UNDERSTAND THIS QUESTION. I DONT EVEN KNOW WHAT FORMULA TO PUT IT IN. I have tried the binomial way but don't understand where the numbers are suppose to go. Please help me with this. thank you so much

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
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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