1. 2. 3.
x×5+122+236=633 320+3×x=620 357÷x=5(dư 7)
x×5 =633-236-122 3×x=620-320 357÷x=12
x×5 =275 3×x=300 x=357÷12
x=275÷5 x=300÷3 x=29,75
x=55 x=100
4. 5. 6.
x÷4=1234(dư 3) 120-(x×3)=30×3 357÷(x+5)=5(dư 7)
x÷4=1237 120-(x×3)=90 357÷(x+5)=12
x=1237×4 x×3=120+90 x+5=357×12
x=4948 x×3=210 x+5=4284
x=210÷3 x=4284-5
x=70 x=4279