6÷3/5=6×5/3=10
1 1/6×6/7=7/6×6/7=1
10-1=9
4 1/5×10/11=21/5×10/11=42/11=
=3 9/11
3 9/11+5 2/11=9
9÷9=1
3/20+1/2-1/15=
=9/60+30/60-4/60=35/60=7/12
7/12×12/49=1/7
3 1/3+2/9=3 3/9+2/9=3 5/9
1/7÷3 5/9=1/7÷32/9=1/7×9/32=
=9/224
1-9/224=215/224
215/224×2 1/3=215/224×7/3=
=215/96=2 23/96
3 1/4-2 23/96=3 24/96-2 23/96=
=1 1/96