3 1/2-5/9=7/2-5/9=63/18-10/18=53/18=2 17/18
1 1/4-1/3=5/4-1/3=15/12-4/12=11/12
1 13/15-2/5=28/15-2/5=28/15-6/15=22/15=
=1 7/15
1 1/3-5/6=4/3-5/6=8/6-5/6=3/6=1/2
2 3/10-4/15=23/10-4/15=69/30-8/30=61/30=
=2 1/30
3 1/8-1/6=25/8-1/6=75/24-4/24=71/24=2 23/24
1/2×1/2÷1 1/2=1/4÷3/2=1/4×2/3=1/6
25×7/15÷25/27=7/15×25×27/25=63/5=12 3/5
5/9 ×2 1/4÷20=5/9×9/4×1/20=1/16