3/5 + 4/15 = 9/15 + 4/15 = 13/15
2/7 + 5/28 = 8/28 + 5/28 = 13/28
3/22 + 6/11 = 6/44 + 24/44 = 30/44 = 15/22
3/4 + 3/20 = 15/20 + 3/20 = 18/20 = 9/10
3/5 + 4/15 = 9/15 + 4/15 = 13/15
2/7 + 5/28 = 8/28 + 5/28 = 13/28
3/22 + 6/11 = 6/44 + 24/44 = 30/44 = 15/22
3/4 + 3/20 = 15/20 + 3/20 = 18/20 = 9/10