10/12=10/12:2=5/6
0,5=5/10=3/6
8/16=8/16:8=1/2=3/6
2/3=4/6
7=7/1=42/6
15/18=15/18:3=5/6
7/21=7/21:7=1/3=2/6
75/90=75/90:15=5/6
1/2=3/6
3/18=3/18:3=1/6
