The manager of a paint supply store wants to estimate the actual a mount of paint contained in 5-litre cans purchased from a nationally known manufacturer. It is known from the manufacturer's specifications that the population standard deviation of the amount of paint is equal to 0.11 litres. A random sample of 200 cans is selected, and the sample mean amount of paint per 5-litre can is 4.97 litres.
Calculate a 90% confidence interval estimate of the population mean amount of paint included in a 5-litre can. Round your answer to two decimal places with the lower bound first and the upper bound last. We are 90% confident that the true population mean amount of paint included in a 5-litre can is between and litres.
If the manager of the same paint supply store wants to estimate the mean amount of paint in a 5-litre can to be within LaTeX: \pm±0.08 litres with 99% confidence, what sample size is needed?