设有x页,则第一天看了0.5x+10页,第二天看了[x-(0.5x+10)]*0.5+10=0.25x-5页,第三天看了[x-(0.5x+10)-(0.25x-5)]*0.5+10=0.125x+2.5页,则有x-0.5x-10-0.25x+5-0.125x-2.5=10即有0.125x=27.5,得x=220这回没错啦! 真倒...