Explanation: Since it tells you she earns $48 in 4 hours, you have to find how much she earns in 1 hour. So you do 48 divided by 4 (12) and that is how much she earns in 1 hour. Since the question is, how much does she earn in 20 hours, you multiply 12 x 20 and that equals 240 which means she earns $240 in 20 hours