X:8=120
x=120*8
x=960
81:x=3
x=81:3
x=27
4x=76
x=76:4
x=19
1)9*8*7=504
2)10*5*8=400
3)8*4*3=96
0.55 (x+4) = 5.5(2x-3)
0.55x + 0.55*4 = 5.5*2x - 5.5*3
0.55x + 2.2 = 11x - 16.5
0.55x -11x = -16.5-2.2
-10.45x = -18.7
x= -18.7 : (-10,45)= 1870/1045 = 374/209 =34/19
х=1 15/19