Classified ads in a newspaper offered 15 used cars of the same make and model for sale. A regression analysis was performed with the age of the car (in years) as the explanatory variable and the asking price (in dollars) as the response variable.
| variable |
coefficient |
SE (Coef) |
| constant |
13815 |
521.19 |
| age |
-1038 |
88.83 |
Construct a 95% confidence interval for the slope of the regression line.