0.4x-0.25（2000-x）=110
问题描述：
0.4x-0.25（2000-x）=110
答
原式=0.4x-0.25×2000+0.25x=110
=0.4x+0.25x-500=110
=0.65x=610
→x=610÷0.65=12200/13≈938.461538
答
0.4x--500+0.25x=110
0.65x=610
x=610/0.65=12200/13