See the survey described in Exercise 1. 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 mean? Assume that reported incomes have a standard deviation of $28,785 (based on data from the U.S. Census Bureau). Is the sample size practical?

Exercise 1

In a Pew Research Center poll of 745 randomly selected adults, 589 said that it is morally wrong to not report all income on tax returns. Construct a 95% confidence interval estimate of the percentage of all adults who have that belief, and then write a statement interpreting the confidence interval.