A Set of Data Consists of the Number of Years $\hat { \mathrm { y } } = 31.6 + 10.9 \mathrm { x }$

Essay

A set of data consists of the number of years that applicants for foreign service jobs have studied German and the grades that they receive on a proficiency test. The following regression equation is obtained: $\hat { \mathrm { y } } = 31.6 + 10.9 \mathrm { x }$ , where $\mathrm { x }$ represents the number of years of study and y represents the grade on the test. What does the slope of the regression line represent in terms of grade on the test?