Lesson 11 Quiz
Use the following information to answer the first 7 questions.An investor with a stock portfolio worth several hundred thousand dollars sued his broker and brokerage firm because he felt that lack of diversification in his portfolio led to poor performance for many years in a row. In an effort to avoid close public scrutiny, the firm agreed to settle the conflict by an arbitration panel. The arbitration panel compared a sample of 39 months of the investor's returns with the average of the Standard & Poor's 500-stock index for the same period in order to determine whether there was a substantial decrease. Their data is in the file RatesOfReturn.xlsx(Links to an external site.).Suppose that you are a member of this arbitration panel. Construct a 95% confidence interval for the true mean return of the investor's portfolio. Record your answers below.Question 1Find the margin of error for the 95% confidence interval for the true mean return of the investor's portfolio. Round your answer accurate to three decimal places.
Question 2Input the lower bound of your confidence interval.(Round your answer accurate to three decimal places.)