1/80×x×2+1/80(x+5)×8=3/4 火速

问题描述:

1/80×x×2+1/80(x+5)×8=3/4 火速

1/80×x×2+1/80(x+5)×8=3/4
1/40×x+1/10(x+5)=3/4
两边乘40
x+4x+20=30
5x=30-20=10
x=10÷5
x=2