2/5 = 4/10=6/15=8/20=10/25=12/30
3/7=6/14=9/27=12/28=15/35=18/42
54/70 = 27/35=108/140=162/210=216/280=270/350
108/246=54/123=324/738=18/41=36/82=540/1230