x/(x+100)=0.2x=0.2 ×(x+100)x=0.2x+200.8x=20 x=25
x/(x+100)=0.2x=0.2(x+100)x=0.2x+20x-0.2x=200.8x=20x=25谢谢
x/(x+100)=0.2x=0.2(x+100)x=0.2x+20x-0.2x=200.8x=20x=25
x=0.2x+200.8x=20x=25
解过程。