1.4X + 1 * (200-X) =200*1.1

问题描述:

1.4X + 1 * (200-X) =200*1.1

1.4X + 1 * (200-X) =200*1.1
1.4x+200-x=220
0.4x=220-200
0.4x=20
x=20/0.4
x=50