推 limitX:是指牌的序號跟點數剛好一樣 11/23 00:09
A well-shuffled ordinary deck of 52 cards is devided randomly
into four piles of 13 each. Counting jack, queen, and king as
11, 12, and 13, respectively, we say that a match occurs in a
pile if the jth card is j. What is the expected value of the
total number of matches in all four piles?
有點看不懂他match的意思..
答案是4
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