PP2 PS

[Jabbos]

Tanya prepared 4 different letters to be sent to 4 different addresses. For each letter, she prepared an envelope with its correct address. If the 4 letters are to be put into the 4 envelope at random, what is the probability that only one letter will be put into the envelope with its corrrect address?

A. 1/24
B. 1/8
C. 1/4
D. 1/3 => 正確
E. 3/8

我選C. 請幫我解釋一下. 感謝

[amazingslim]

http://www.formosamba.com/phpBB3/viewtopi ... ight=Tanya

可以使用搜尋喔，我是用Tanya搜尋

[Jabbos]

新手剛上來. 以後會注意. 多謝link