The manager of a paint supply store desires to estimate actual amount of paint contained in 1 gallon cans purchased from the nationally known manufacturer. The manufacturer's specifications stated that the standard deviation of amount of paint is equal to 0.02 gallon. A random sample of 50 cans is selected and sample mean amount of paint per 1 gallon can is 0.995 gallon.
a. Make a 99% confidence interval estimate of population mean amount of paint included in 1 gallon can.
b. On the basis of such result do you think the manager has the right to complain to manufacturer? Why?
c. Must you suppose that the population amount of paint per can is normally distributed here? Describe
d. Develop a 95% confidence interval estimate. How does this change your answer to (b)?