=0.75*0.25*0.25+0.25*0.75*0.25+0.25*0.25*0.75

來源: 於 2010-01-11 20:09:22 [舊帖] [給我悄悄話] 本文已被閱讀：次

=0.75*0.25*0.25+0.25*0.75*0.25+0.25*0.25*0.75
=9/64