C)
x-140:35=270
x-140=270x35
x-140=9450
x=9450+140
x=9590
a) (x + 74) - 318 = 200
x + 74 = 200 + 318
x + 74 = 518
x = 518 - 74
x = 444
b) 3636 : (12.x - 91) = 36
3636 = 36(12.x - 91)
3636 : 36 = 12.x - 91
101 = 12.x - 91
101 + 91 = 12.x
192 = 12.x
192 : 12 = x
16 = x
x = 16
c) x - 140 : 35 = 270
x - 4 = 270
x = 270 + 4
x = 274
\(a.\left(x+74\right)-318=200\)
\(\left(x+74\right)=200+318\)
\(x+74=518\)
\(x=518-74\)
=> \(x=444\)
\(b.3636:\left(12x-91\right)=36\)
\(\left(12x-91\right)=3636:36\)
\(12x-91=101\)
\(12x=101+91\)
\(12x=192\)
\(x=192:12\)
=> \(x=16\)
\(c.x-140:35=270\)
\(x-4=270\)
\(x=270+4\)
=> \(x=274\)
Chúc bạn học tốt!