Understanding Basic Statistics 6th Edition by Charles Henry Brase,Corrinne Pellillo Brase

Exercise 15

New Car: Negotiating Price Suppose you are interested in buying a new Toyota Corolla. You are standing on the scales lot looking at a model with different optioms. The list price on the vehicle. As a salesperson approaches, you wonder what the dealer invoice price is for this model with its options. The following data are based on information taken from Consumer Guide (Vol. 677). Let x be the list price (in thousands of dollars) for a random selection of Toyota Corolla of different models and options. Let y be the dealer invoice (in thousands of dollars) for the given vehicle.
(a) Verify that x = 79.6, y = 72.1, x 2 = 1057.76, y 2 = 867.49, xy = 957.84, and r 0.956.
(b) Use a 1% level of significance to test the claim that 0.
(c) Verify that S e 0.1527, a 1.965, and b 0.758.
(d) Find the predicted dealer invoice when the list price is x = 14 (thousand dollars).
(e) Find a 85% confidence interval for y when x = 14 (thousand dollars).
(f) Use a 1% level of significance to test the claim that 0.