SOLUTION: The Body-mass index (BMI) of all American 20-something women is believed to follow a normal distribution with a standard deviation of 6.5. Find how many 20-something women should b

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Question 867522: The Body-mass index (BMI) of all American 20-something women is believed to follow a normal distribution with a standard deviation of 6.5. Find how many 20-something women should be randomly sampled if we want the mean BMI of such a sample to be within 1 BMI unit of the population mean with 95 percent confidence.
Answer by stanbon(75887) (Show Source):
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The Body-mass index (BMI) of all American 20-something women is believed to follow a normal distribution with a standard deviation of 6.5. Find how many 20-something women should be randomly sampled if we want the mean BMI of such a sample to be within 1 BMI unit of the population mean with 95 percent confidence.
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n = [z*s/E]^2 = [1.96*6.5/1]^2 = 163 when rounded up
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Cheers,
Stan H.
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