80%x+(500-X)60%=500*75% 急

问题描述:

80%x+(500-X)60%=500*75% 急

80%x+300-60%x=375
20%x=75
x=375
很简单……

80%x+(500-X)60%=500*75%
80%x+300-60%x=375
20%x=75
x=375

0.8x+500*0.6-0.6x=375
0.2x=375-300
0.2x=75
x=75/0.2
x=375

x=375

80%x+(500-X)60%=500*75%
08X+0.6(500-X)=500*.075
08X+0.6*500-0.6X=375
0.2X+300=375
0.2X=75
X=75/0.2
X=375