1/3+1/5=8/15
1/3-1/4=1/12
2 1/9+1 1/3= 3 4/9
2 1/2-1 1/3= 1 1/6
3- 1 2/5=8/5
4 7/15-2 5/12= 2 2/15
4 3/14+1 1/2=5 10/14
1 2/3+ 2 7/8= 4 13/24
1-5/17= 12/17
3 1/14-2 5/21=5/6
4 13/18-3 7/9=17/18
1/2-4/17=9/34
9/49+5/7=44/49
1 7/12-3/16=67/48
3 4/5-1 1/3=2 7/15
