3/5 + 3/15 - 3/10
7/9 + 15/ 15
5/6 - 3/8
3/4 + 3/10
31/21 - 3/14
3/4 + 2/5 + 1/6
6/7 + 8/3
3/5 - 1/3
15/30
21/20
11/24
4/15
74/21
53/42
41/45
79/60
