更新1:
To : 自由自在 Can you please explain why it is 5! x 5!, not simply 5!? Where is the second 5! come from? Thanks.
Permutation
2010-12-21 5:28 am
4 books and 6 magazines are to be arranged in 2 rows of 5 copies each. At least 2 books must be on the first row and at least 2 magazines must be on the second row. What is the total number of arrangements?
回答 (1)
2010-12-21 5:41 am
✔ 最佳答案
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2010-12-21 21:42:03 補充：
The first 5! is the ordering of the first row and the second 5! is the ordering of the second row.
收錄日期: 2021-04-23 23:25:35
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20101220000051KK01156