1)40×3-5=195
75÷3+100=125
150-15×3=104
2)673+100+427+3×100=1200+300=1500
3)(x+38)-59=125
x+38=125+59
x+38=184
x=184-38
x=146
(146+38)-59=125
125=125
3(x+15)=186
x+15=186÷3
x+15=62
x=62-15
x=47
3×(47+15)=186
186=186
2x+3x+16=51
5x+16=51
5x=51-16
5x=35
x=35÷5
x=7
2×7+3×7+16=51
51=51
x÷4+5=16
x÷4=16-5
x÷4=11
x=11×4
x=44
44÷4+5=16
16=16
11×(x-9)=121
x-9=121÷11
x-9=11
x=11+9
x=20
11×(20-9)=121
121=121
4)(130+112)÷121=x
242÷121=x
x=2
(130+112)÷121=2
2=2