Question: A publishing company has just published a new college textbook. Before the company

decides the price at which to sell this textbook, it wants to know the average price of all

such textbooks in the market. The research department at the company took a sample of

36 comparable textbooks and collected information on their prices. This information

produced a mean price of $70.50 for this sample. It is known that the standard deviation

of the prices of all such textbooks is $4.50.

(a) Provide a point estimate of the mean price of all such college textbooks.

(b) Construct a 90% confidence interval for the mean price of all such college textbooks.