Question 8.336

taxreturn

10. Tax Returns. In Example 10 in Section 3.2, Ashley and Brandon worked at an accounting firm preparing tax returns. Their Chief Accountant kept careful track of the amount of time (in hours) for all the tax returns that they prepared in the last week of March, shown in the accompanying table. Assume both data sets are normally distributed.

Ashley 5 7 8 9 11
Brandon 3 5 7 11 14

485

  1. Construct and interpret a 95% confidence interval for the population standard deviation of Ashley's preparation time.
  2. Construct and interpret a 95% confidence interval for the population standard deviation of Brandon's preparation time.