1 5/12-7/10=17/12-7/10=85/60-42/60=43/60
7 7/8-1 9/10=63/8-19/10=315/40-76/40=239/40=5 39/40
12 3/10-5 11/15=123/10-86/15=369/30-172/30=197/30=6 17/30
5 1/9+3 2/5=46/9+17/5=230/45+153/45=383/45=8 23/45
1-2/7=7/7-2/7=5/7
1/2+3/5=5/10+6/10=11/10=1 1/10