IRS. In a random survey of 226 self-employed individuals, 20 reported having had their tax returns audited by the IRS in the past year. Estimate the proportion of self-employed individuals nationwide who’ve been audited by the IRS in the past year.

a) Check the assumptions and conditions (to the extent you can) for constructing a confidence interval.

b) Construct a 95% confidence interval.

c) Interpret your interval.

d) Explain what “95% confidence” means in this context.