两边乘(150-3x)(150-x)
4(150-x)=8(150-3x)
150-x=2(150-30x)
150-x=300-60x
59x=150
x=150/59 两边乘(150-3x)(150-x)
4(150-x)=8(150-3x)
150-x=2(150-30x)
150-x=300-60x
59x=150
x=150/59