12:310=
58:512=
89:2710=
8:45=
5:1 14=
1 23:1 19=

12:310=1/2 • 10/3 = 5/3 = 1 2/3
58:512= 5/8 • 12/5 = 3/2 = 1 1/2
89:2710= 8/9 • 10/27 = 80/243
8:45= 8 • 5/4 = 10
5:1 14= 5 • 4/5 = 4
1 23:1 19= 5/3 • 9/10 = 3/2 = 1 1/2

вот. надеюсь почерк поймешь