simple random sample of voters will be taken in a large state. Researchers will use the methods of our course to construct an approximate 95% confidence interval for the percent of the state’s voters who will vote for Candidate X. The minimum sample size needed to ensure that the width of the interval (right end minus left end) is at most 6% is

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koikkara · Answer

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koikkara · Answer

If you look close to your question, if  minimum sample size required to make the width at-most is 6%. Hence we can have min. sample size if we have maximum SE which is possible for max interval possible at 0.5.as u have given 95% c.i. its z value is 1.96 and hence i compute it = 

96	imes \sqrt{( 0.5	imes0.5)}\div n = 0.3

koikkara · Answer

See Equation (Picture)

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