7%x+10%（80-x）=6.5

分类: 作业答案 • 2021-12-03 16:24:37

问题描述：

7%x+10%（80-x）=6.5

答

7%x+10%（80-x）=6.5
0.07x+8-0.1x=6.5
0.1x-0.07x=8-6.5
0.03x=1.5
x=1.5÷0.03
x=50

不懂可追问,有帮助请采纳,谢谢!