1.On a bookshelf there are 3 different mathematics books and 5 different computer science books.
(a)Find the possible number of arrangements of the books on the bookshelf.
(b)In how many ways can the books be arranged so that all the mathematics books are put together?
(c)Find the number of ways that all the computer science books will not be together.
help ~~
2007-01-16 6:40 am
回答 (3)
2007-01-16 7:44 pm
✔ 最佳答案
(a) No. of arrangements= 8!
= 40320
(b) No. of arrangements
= 6! x 3!
= 720 x 6
= 4320
(c) No. of arrangements
= 8! - 4! x 5!
= 40320 - 24 x 120
= 37440
2007-01-16 11:48:46 補充：
matthewlcy(c) part 係話"all" the computer science books所以係有得分隔的
2007-01-16 11:51:42 補充：
yan12794全錯了8! = 40320下次小心點吧! ^^(b),(c) part亦不能單單乘3同乘5math書同computer science書都有得排位
參考: 在下自修既M&S
2007-01-16 7:54 am
1. 50320
2. 2160
3. 40200
2. 2160
3. 40200
2007-01-16 6:58 am
a. 8!
b. 6!
c. 0 因為5本書最少都要有４本書先可以隔住晒唔put together,所以得3本Maths 書無可能完全分隔5本Comp書
b. 6!
c. 0 因為5本書最少都要有４本書先可以隔住晒唔put together,所以得3本Maths 書無可能完全分隔5本Comp書
參考: me
收錄日期: 2021-04-12 21:25:59
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