120 * х = 240,
x=240:120
x=2
120*х = 80 * 3,
120x=240
x=240:120
x=2
60 * х = 240 : 2,
60x=120
x=120:60
x=2
х * 2 = 240 * 2,
2x=480
x=480:2
x=240
400 : у = 8,
y=400:8
y=50
(500 - 100) : у = 8,
400:y=8
y=400:8
y=50
400 : у = 320 - 302,
400:y=18
y=400:18
y=22 2/9
z : 7 = 80,
z=80*7
z=560
z : 7 = 40 * 2
z:7=80
z=80*7
z=560