是不是x/(1+15%)-y/(1-10%)=500?x/1.15-y/0.9=500x=y+950(y+950)/1.15-y/0.9=500y/1.15+950/1.15-y/0.9=500y*(1/0.9-1/1.15)=500-950/1.15=-7500/2350y/207=-7500/23y=-1350x=y+950=2300