17 + 9/13 = 17 9/13
3 1/5 - 1 3/5 = 2 6/5 - 1 3/5 = 1 3/5
2 4/9 - 1 7/9 = 1 13/9 - 1 7/9 = 6/9 = 2/3
1 5/7 + 6/7 = 2 5/7
5 8/13 + 4 7/13 = 9 15/13 = 10 2/13
17 + 9/13 = 17 9/13
3 1/5 - 1 3/5 = 2 6/5 - 1 3/5 = 1 3/5
2 4/9 - 1 7/9 = 1 13/9 - 1 7/9 = 6/9 = 2/3
1 5/7 + 6/7 = 2 5/7
5 8/13 + 4 7/13 = 9 15/13 = 10 2/13