• Best-fit Line and Regression Line
• Predictions from Best-fit Lines

By observing another set of data values, Tasha used a calculator for the tire diameter at the tread and circumference data and got an equation for the least-squares line: = 0.1 + 3.1x.

Using this equation to predict circumference from diameter at the tread, the circumference for a 30-inch diameter at the tread tire would be __________.

Please enter your answer as a real number, rounded to the tenths place, for example, 3.5 or -10.2.