Question

The table represents the interest rates, r, at various years and the corresponding median house value, v. What does the slope of the trend line equation v = 2.4r + 154 represent?

Answer 1

For an increase of 1% in interest rate, the median house value will increase by approximately 2.4 thousand dollars.

Explanation:

Slope is rate of change.

In this situation, r, the interest rate, is the independent variable and v, the median house value, is the dependent variable. The slope is multiplied by r; this means for every increase of 1 in the independent variable, the dependent variable will increase by the amount of the slope.

For this situation, this means that for every increase of 1 in interest rate, the median house value will increase by 2.4.

Answer 2

The answer is c. v=2.4r+154. v is the dependent variable, and r is the independent variable. From the equation above, if we increase r by 1 unit, v will increase by 2.4 (154 doesn't affect because it's always a constant). The unit of r is %, while the unit of v is thousand, therefore if we increase interest rate by 1%,  the median house value increases by 2.4 thousand.