Question
The following table gives the age (in years) of 36 randomly selected U.S. millionaires. The sample...
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The following table gives the age (in years) of 36 randomly selected U.S. millionaires. The sample mean x−=58.53 years. Assume that the standard deviation of ages of all U.S. millionaires is 13.0 years. (See data on file: M07_Age_Millionaire_Q9.txt.)
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Obtain a 95% confidence interval for μ, the mean age of all U.S. millionaires.
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Interpret the confidence interval obtained in part (a).
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According to the confidence interval obtained in part (b), could you claim that average age of all U.S. millionaires is above 55 years? Explain your answer.
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Determine the number of millionaires should be picked to guarantee that the error of x−in estimating μ is at most 0.5 years with 98% confidence.
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