1/4+3/5=5/20+12/20=17/20
9/11-2/5=45/55-22/55=32/55
13/16-9/32=26/32-9/32=17/32
3/28+5/14=3/28+10/28=13/28
14/15-7/10=28/30-21/30=7/30
3/8+1/6=9/24+4/24=13/24
9/25-7/20=36/100-35/100=1/100
37/42-17/24=
11/24-3/6=11/24-12/24=-1/24
9/16+7/24-3/8=27/48+14/48-18/48=23/48
1/3-1/6+1/4=8/24-4/24+6/24=10/24
2/5+4/15-5/9=18/45+12/45-25/45=5/45=1/9