20/8=5/2=2 1/2
15/10=3/2=1 1/2
28/21=9/7=1 2/7
10/6=5/3=1 2/3
14/4=7/2=3 1/2
40/15=8/3=2 2/3
4+8>13-8
9+6>7+7
5+8>12-5
9+8>18-9
12-5=11-4
14-7<7+6