①0.125×32×2.5
=0.125×(8×4)×2.5
=(0.125×8)×(2.5×4)
=1×10
=10
②0.8×6.3-0.8×3.8
=0.8×(6.3-3.8)
=0.8×2.5
=2
③2x+10.5=26.5
2x+10.5-10.5=26.5-10.5
2x÷2=16÷2
x=8
④x÷(3.4×0.5)=30
x÷1.7=30
x÷1.7×1.7=30×1.7
x=51
⑤43x-2x=30.75
41x=30.75
41x÷41=30.75÷41
x=0.75
⑥120-2x=45.6
120-2x+2x=45.6+2x
2x+45.6-45.6=120-45.6
2x÷2=74.4÷2
x=37.2