Question

Bryce wrote the linear regression equation y = 1.123 x minus 6.443 to predict the armspan, y, of a person who is x inches tall. Riley has an armspan of 67.5 inches. Which is the best prediction of Riley’s height?
54.36 inches
65.84 inches
66.55 inches
69.36 inches

Answer 1

Solve y = 1.123x − 6.443 for x: x = (y + 6.443)/1.123.
x = (67.5 + 6.443)/1.123 = 73.943/1.123 ≈ 65.84 inches.

Answer: 65.84 inches.