Ranching: Cattle You are the foreman of the Bar-S cattle ranch in Colorado.

A neighboring ranch has calves for sale, and you are going to buy some to add to the Bar-S herd. How much should a healthy calf weigh? Let x be the age of the calf (in weeks), and let y be the weight of the calf (in kilograms).

The following information is based on data taken from The Merck Veterinary Manual (a reference used by many ranchers).

x 1 3 10 16 26 36 y 42 50 75 100 150 200 Complete parts

(a) through (e), given x 5 92, y 5 617, x2 5 2338, y2 5 82,389, xy 5 13,642, and r < 0.998.

(f) The calves you want to buy are 12 weeks old. What does the least-squares line predict for a healthy weight?