In the simple linear regression model for average SAT score, (
total) as a function of average teacher salary (
salary), the fitted coefficient was -5.02 points per thousand dollars. This suggests that for every additional thousand dollars of salary for teachers in a particular state, the expected SAT score for a student from that state is about 5 points lower.
In the model that includes the percentage of students taking the SAT, the coefficient on
salary becomes 1.84 points per thousand dollars. Choose the correct interpretation of this slope coefficient.