Question 8.70

deepwaterclean

70. Deepwater Horizon Cleanup Costs. The following table represents the amount of money distributed by BP a random sample of six Florida counties for cleanup of the Deepwater Horizon oil spill, in millions of dollars.4 Assume .

County Cleanup costs
($ millions)
Broward 0.85
Escambia 0.70
Franklin 0.50
Pinellas 1.15
Santa Rosa 0.50
Walton 1.35
  1. Assess the normality of the data, using a normal probability plot. Confirm that the conditions for constructing a interval are met.
  2. Assuming that the cleanup costs are normally distributed, construct and interpret a 95% confidence interval for the population mean cleanup cost.
  3. Calculate and interpret the margin of error for the confidence interval in part (b).
  4. How large a sample size do we need to estimate to within $50,000 with 95% confidence?