梨+2/5×梨=苹果1.算术凳庆行:运进的枣哗差腊梨有:280/(1+2/5)=200筐2.方程设运进的梨有x筐x+2/5*x=280x=200筐
蛇李X框280-X=2/5X X=200
280=X(1+0.4)求出X=200;
280-(280x2/5)
280=7x/5x=200280/(7/5)=200