The average return for large-cap domestic stock funds over the three years 2009-2011was 14.4% (AAIIJournal, February 2012). Assume the three-year returns were normally distributed across funds with a standard deviation of 4.4%. a. What is the probability an individual large-cap domestic stock fund had a three-year return of at least 20%? b. What is the probability an individual large-cap domestic stock fund had a three-year return of 10% or less? c. How big does the return have to be to put a domestic stock fund in the top 10% for the three-year period?

7. A student plans to go sledding on the first snow day in December. The chance of snow on any given day is 13%. What is the standard deviation of the date that the first snow to occurs?

An insurance company wants to make sure that its best customers (those with lowest value of insurance claims) stay with the company. To achieve this goal, the company plans to offer a 10% discount on the annual health insurance premium for customers with the lowest 20% of annual health care expenses. If the average annual health care expenses for a family of four is $3,650 with a standard deviation of $975, what is the amount of the maximum annual health care expense that will qualify for the proposed discount?

A certain brokerage house wants to estimate the mean daily return on a certain stock. A random sample of 20 days yields the following return percentages. 1.09, -1.09, -0.14,-0.03,1.76,-1.59,-1.46 , 2.13, 1.96, 2.01,-0.91,0.64,-2.41, 1.81, –0.25, -0.46,0.37, -0.21, 1.39,0.68 Send data to calculator Send data to Excel If we assume that the returns are normally distributed, find a 95% confidence interval for the mean daily return on this stock. Then find the lower limit and upper limit of the 95% confidence interval. Carry your intermediate computations to at least three decimal places. Round your answers to one decimal place. (If necessary, consult a list of formulas.) Lower limit: Upper limit: