plis to jedno z matmy tylko dolna linijka

9/20 = 27/60
9/20 = 36/80
9/10 = 54/60
9/10 = 36/40
3/12 = 1/4
1/4 = 15/60
1/4 = 36/144
6/15 = 2/5
2/5 = 24/60
2/5 = 36/90
12/30 = 4/10 = 2/5
4/10 = 24/60
4/10 = 36/90
:)