1) 5/6 = 15/2x - 3=5/6=15/2х-3
5(2х-3)=15*6
10х-15=90
10х=105
х=10,5
2) 12:4/5х = 20 1/4
12*5х/4 = 20*4/1
60*х/4 = 80
60х = 320
х=16/3
х=5 1/3
