1/2 + 2/3= 3/6 + 4/6 = 7/6= 3/2= 1 ¹/6
1/4 + 2/5= 5/20 + 8/20=13/20
2/3+1/4=8/12+3/12=11/12
3/4+2/5=15/20+8/20=23/20=1 ³/20
5/7-1/6 =30/42-7/42=23/42
3/4-1/3 = 9/12-4/12 = 5/12
1/8+1/4 = 1/8 + 2/8 = 3/8
2/3-5/9=6/9-5/9 = 1/9
1/2-5/12=6/12-5/12=1/12
5/12-2/9=15/36-8/36=7/36
1/8+7/12=3/24+14/24=17/24
3/4-1/6=9/12-2/12=7/12
5/9+3/4=20/36+27/36=47/36= 1 11/36
23/40-3/8=23/40-15/40=8/40=1/5
9/35-3/28=36/140-15/140=21/140=3/20