The constant of variation the question is asking for is basically your hourly rate. You get $110 for working 20 hours, so set up a proportion like this: 110/20 = x/1 where x is the amount you earn per hour of working. Use algebra to solve: 110 = 20x → x = 5.5 which means that your hourly rate (or constant of variation) is 5.5 (or $5.50)