SOLUTION: A researcher wishes to estimate the proportion of adults who have high-speed Internet access. What size sample should be obtained if she wishes the estimate to be within 0.04 wi
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Question 1151506: A researcher wishes to estimate the proportion of adults who have high-speed Internet access. What size sample should be obtained if she wishes the estimate to be within 0.04 with 95% confidence if
(a) she uses a previous estimate of 0.52?
(b) she does not use any prior estimates?
You can put this solution on YOUR website! Margin of error(ME) = 0.04
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critical value(CV) for a 95% confidence is 1.96
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sample size(n) = ( CV^2 * p * (1-p) ) / ME^2
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(a) n = ( 1.96^2 * 0.52 * (1-0.52) ) / 0.04^2 = 599.2896 is approximately 600
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(b) when proportion is not known use p = 0.50
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n = ( 1.96^2 * 0.50 * (1-0.50) ) / 0.04^2 = 600.25 is approximately 601
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