To answer this question, you have to add 6 2/5 and 7 13/15 and subtract 13 7/15 from that answer. First, add 6 and 7 together to get 13. Then add 6/15, 2/5*3/3, and 13/15 together. You get 19/15, and if you simplify it 1 4/15. You'd then add 1 4/15 to 13, making it 14 4/15. Then subtract 13 7/15 from 14 4/15. For this one you would want to take change 14 4/15 to 13 19/15 so you can more easily subtract. If you subtract 13 from 13 you would get zero, so all you have to do now is subtract 7/15 from 19/15. Finally, you would get 12/15, 0r 3/5 as your answer.
