张文涓逝世:这道题用简便算法,怎么算呀。

来源:百度文库 编辑:杭州交通信息网 时间:2024/05/10 09:29:39
48/49×48

48/49X(49-1)
=48+48/49
=48又48/49

=48*(49+1)
=48*50
=2400

48/49*48
=(1-1/49)*48
=48-48/49
=47又1/49
=2304/49

(49-1)*(49-1)/49=
(49*49-2*49+1)/49=
49-2+1/49=
47+1/49

48/49X(49-1)
=48+48/49
=48又48/49