大哥用文字打出来或者用手机拍照把!
把x=1/4代入方程(3X+1)/5=1-(X+●)/5得(3×1/4+1)/5=1-(1/4+m)/5解:3×1/4+1=5-(1/4+m) m=3被污染的数字是3
答案是4/1还是1/4?