(300)/(x-2)— (300)/x=300x-300(x-2)/x(x-2)=600/x(x-2)=600/x^2-2x 百分之百对,老师改过的
(300)/(x-2)— (300)/x=300x-300(x-2)/x(x-2)=600/x(x-2)=600/x^2-2x
(300)/(x-2)— (300)/x
:设几名同学为x-2名。原来付:300/x-2元现在付:300/x元300/x-300/x-2