Question

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 calves 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).

x	1	2	8	16	26	36
y	47	53	75	100	150	200

Complete parts (a) through (e), given Σx = 89, Σy = 625, Σx² = 2297, Σy² = 83,143, Σxy = 13,453, and r ≈ 0.996.

(c) Find x, and y. Then find the equation of the least-squares line  = a + bx. (Round your answers for x and y to two decimal places. Round your answers for a and b to three decimal places.)

x	=
y	=
	=	+   x

(f) The calves you want to buy are 20 weeks old. What does the least-squares line predict for a healthy weight? (Round your answer to two decimal places.)
_______ kg

Answer 1

a. Regression equation

b. The predicted value of y given x = 20.

predict for a healthy weight = 126.2874