Last week Fred had 34 dollars and Jason had 31 dollars. They washed cars over the weekend and now Fred has 32 dollars and Jason has 41 dollars. How much money did Jason make over the weekend?
Fred had 34 dollars and Jason had 31 dollars. 

This means that, in total, they had 65 dollars. 

After they washed cars over the weekend, Fred had 32 dollars and Jason had 41 dollars. 

This means that, in total, they had 73 dollars. 

So, Jason made 8 dollars over the weekend.