fractions:
5/15 - 6/18=...
2/1-1/4=...
6/8+10/15-10/12=...
2.1/3=...
3.2/5=...
12/15.5/6=...
7/10.3=...
14/9.6/5=...
2/9.4=...
Merci beaucoup :)