SOLUTION: A researcher wants to make a 95% confidence interval for the population proportion. A preliminary sample produced the sample proportion equal to .29. How large should the sample si

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Question 311666: A researcher wants to make a 95% confidence interval for the population proportion. A preliminary sample produced the sample proportion equal to .29. How large should the sample size be so that the maximum error of estimate is within .04 of the population proportion?
Answer by stanbon(75887)   (Show Source): You can put this solution on YOUR website!
A researcher wants to make a 95% confidence interval for the population proportion. A preliminary sample produced the sample proportion equal to .29. How large should the sample size be so that the maximum error of estimate is within .04 of the population proportion?
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n = [z/E]^2*(pq)
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n = [1.96/0.04]^2(0.29)(0.71) = 495 when rounded up
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Cheers,
Stan H.

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