One measure of the poverty level of a county is the percentage of children who qualify for free lunches at school.

One measure of the poverty level of a county is the percentage of children who qualify for free lunches at school. The following spreadsheet includes this "% pupils with free lunch" variable (X) as well as a composite measure of how well the county's pupils scored on the SAT college entrance exam (average system SAT, Y). Based on previous studies, you believe counties with a higher % of students with free lunch will have lower SATs. 

County