13/18+7/12=26/36+21/36=47/36=1 11/36
5/7-3/5=25/35-21\35=4\35
5/6-3/8-1/12=40/48-18/48-4/48=18/48=9/24=3/8
13/18+7/12=26/36+21/36=47/36=1 11/36
5/7-3/5=25/35-21\35=4\35
5/6-3/8-1/12=40/48-18/48-4/48=18/48=9/24=3/8