6х+2*3х=270
11,2х+3,7=7,06
11,2х=7,06-3,7
11,2х=3,36
х=3,36/11,2
х=0,3
11/20×4/9 = 44/180 = 11/45
11/50×8/9 = 88/450 = 44/225
3/11×44 = 132/11 = 12
3 1/2×1 1/7 = 56/14 = 4