Last week Fred had 26 dollars and Jason had 19 dollars. Fred washed cars over the weekend and now has 12 dollars and Jason did not work. How much money do they have together now?
Fred had 26 dollars and Jason had 19 dollars. 

That means that, together, they had 45 dollars. 

Fred washed cars over the weekend and now has 12 dollars. 

That means that he made 14 dollars from washing cars. 

Jason did not work. 

That means that he has the same amount of money as he did before. 

Now, let's put it all together: 

Fred had 26 dollars and Jason had 19 dollars. 

Fred washed cars over the weekend and now has 12 dollars. 

Jason did not work. 

That means that, together, they have 57 dollars.