In problem 6-5, suppose that a 99% confidence interval is required. Compute the new interval, and compare it with the 95% confidence interval you computed in problem 6-5.

In problem A real estate agent needs to estimate the average value of a residential property of a given size in a certain area. The real estate agent believes that the standard deviation of the property values is σ = $5,500.00 and that property values are approximately normally distributed. A random sample of 16 units gives a sample mean of $89,673.12. Give a 95% confidence interval for the average value of all properties of this kind.