Diamond weight and price The weight (in carats)

and the price (in millions of dollars) of the 9 most expensive diamonds in the world was collected from www.elitetraveler.com. Let the explanatory variable x = weight and the response variable y = price. The regression equation is yn = 109.618

+ 0.043x.

a. Princie is a diamond whose weight is 34.65 carats. Use the regression equation to predict its price.

b. The selling price of Princie is $39.3 million. Calculate the residual associated with the diamond and comment on its value in the context of the problem.

c. The correlation coefficient is 0.053. Does it mean that a diamond’s weight is a reliable predictor of its price?