The Wall Street Journal reported on several studies that show massage therapy has a variety of health benefits and it is not too expensive. A sample of 10 typical one-hour massage therapy sessions showed an average charge of $59. The population standard deviation for a one-hour session is s 5 $5.50.
a. What assumptions about the population should we be willing to make if a margin of error is desired?
b. Using 95% confidence, what is the margin of error?
c. Using 99% confidence, what is the margin of error?