Susan decorates her Chrismas tree using a series of light bulbs.She has 5 red,4 yellow and 2 blue bulbs available.
(a)( i ) If she uses all the light bulbs,how many different arrangements can the make?
( i i ) In ( i ),how many of the arrangement will the two blue bulbs be separated?
(b)If she only uses 10 of the bulbs,how many different arrangements can she make?
數學與統計
2007-09-16 3:39 am
回答 (1)
2007-09-16 4:30 am
✔ 最佳答案
a(i) 11!/5!4!2! = 6930(ii) 6930-10!/5!4! = 5670
b 10!/5!4! + 10!/5!3!2! + 10!/4!4!2! = 6930
收錄日期: 2021-04-25 22:00:43
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https://hk.answers.yahoo.com/question/index?qid=20070915000051KK04289