作者angrycute (哈)
站內NTUE-ME94
標題[問題] 機率與統計
時間Sun Apr 1 20:35:40 2007
A group of 5 boys and 10 girls is lined up in random order-that is,each of
the 15! permutations is assumed to be equally likely.
(a)What is the probability that the person in the 4th position is a boy?
(b)What about the person in the 12th position?
(c)What is the probability that a particular boy is in the 3rd position?
會的話請幫我附上詳細解說!!
謝謝你^_^
--
※ 發信站: 批踢踢實業坊(ptt.cc)
◆ From: 59.125.185.112