Условие см. в приложении.
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1) х/4 = 5 2) 105/y = 7 3) (x + 12)/6 = 14
x = 5 * 4 y = 105 : 7 х + 12 = 14 * 6
x = 20 y = 15 x + 12 = 84
20 : 4 = 5 105 : 15 = 7 х = 84 - 12
5 = 5 7 = 7 х = 72
(72 + 12) : 6 = 14
84 : 6 = 14
14 = 14
70*x=630
x=630/70
x=9
y-189=2500/25
y=100+189
y=289
460-c=180*105
c=460-18900
c=-18440