注:*是乘号,X和Y是未知数,3/5是5分之3,1.3/5是带分数1又5分之31. (X+3/5)*1/2=42. 1.3/5+1/2X=103. [24.8X*(1-1/3)+16*1/2X]*12.5%=4604.240+Y/240+20%Y=70%第二个更正下,是1.3/5*5+1/2X=10