Question 240150: In a survey of 745 randomly selected adults, 589 said that it's morally wrong to not report all income on tax returns. Assume that you must conduct a survey to determine the mean income reported on tax returns and you have access to actual tax returns. How many randomly selected tax returns must you survey if you want to be 99% confident that the mean of the sample is within $500 of the true population? Assume the reported incomes have a standard deviation of $28,785.
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! In a survey of 745 randomly selected adults, 589 said that it's morally wrong to not report all income on tax returns. Assume that you must conduct a survey to determine the mean income reported on tax returns and you have access to actual tax returns. How many randomly selected tax returns must you survey if you want to be 99% confident that the mean of the sample is within $500 of the true population? Assume the reported incomes have a standard deviation of $28,785.
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n = [z*s/E]^2
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n = [2.576*28785/500]^2 = 21990.07
Round up to 21991
Cheers,
Stan H.
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