Question

Using the Regression Line to Make a Prediction

The ordered pairs show (height in inches, men’s shoe size).

(70, 9.5) (67, 8) (69, 9) (72, 11.5) (68, 7.5) (60, 6) (71, 11)

Use the regression calculator to generate the regression equation used to make predictions.

What is the approximate height of a man who wears a size 7 shoe? Round to the nearest whole number.

inches

Answer 1

The least-squares regression (shoe size y vs. height x) is approximately
y = -21.29 + 0.4436 x.

For shoe size y = 7, solve x = (y - a)/b:
x ≈ (7 - (-21.29)) / 0.4436 ≈ 63.8 inches.

Rounded to the nearest whole number: 64 inches.