A linear model can be used to describe the relationship between fuel economy(mpg) and horsepower (hp) for certain automobile models.

mpg=46.868-0.0838 hp R^2=75.5%

1) Give the symbol and the value of the correlation coefficient.

2)What would the gas mileage be for a car with a 140 horsepower engine.

3) Interpret with a sentence in context the meaning of R^2?

4) Interpret with a sentence in context the meaning of the slope.

5)Interpret with a sentence in context the meaning of the y-intercept.

6)Interpret with a sentence in context the meaning of particular car having a negative residual.

1 answer

Here are a few hints to help you with some of your questions.

Coefficient of Determination is the correlation coefficient squared. To find the correlation coefficient, take the square root of .755 (75.5% converted to a decimal) for your answer. The Coefficient of Determination shows the strength of the relationship between two variables.

To find mpg, substitute 140 for hp in the equation and solve.

In the equation mpg=46.868-0.0838 hp:
46.868 represents the y-intercept and -0.0838 the slope.

I hope this will help get you started.