作者love113w (free)
看板Statistics
标题[问题] 机率问题
时间Tue Aug 2 12:07:46 2016
如果是跟统计软体有关请重发文章，使用程式做为分类。
统计软体，如SPSS, AMOS, SAS, R, STATA, Eviews，请都使用程式做为分类
请详述问题内容，以利板友帮忙解答，过短文章依板规处置，请注意。
为避免版面混乱，请勿手动置底问题，擅用E做档案编辑
A company takes out an insurance policy to cover accidents that occur at its
manufacturing plant. The probability that one or more accidents will occur
during any given month is 0.60. The numbers of accidents that occur in different months
are mutually independent.
Calculate the probability that there will be at least four months in which no
accidents occur before the fourth month in which at least one accident occurs.
解答是算
in the first seven months there must be at least four with no accidents
为何是7个月阿? 题目内好像也没有提到
谢谢
--
※ 发信站: 批踢踢实业坊(ptt.cc), 来自: 140.135.40.201
※ 文章网址: https://webptt.com/cn.aspx?n=bbs/Statistics/M.1470110869.A.26C.html
1F：→ kerwinhui: generalised pigeonhole...7个月一定是有4个月无意外或 08/02 12:45
2F：→ kerwinhui: 4个月有意外 08/02 12:45
3F：→ kerwinhui: (至少4个月) 08/02 12:46
4F：→ kerwinhui: 6个月还有可能是3-3 08/02 12:46
5F：→ love113w: 抱歉 本人有点笨... 请问一下 generalised pigeonhole 08/02 14:09
6F：→ love113w: 是甚麽意思呢? 然後又是如何看出来要算7个月? 谢谢 08/02 14:10
7F：→ wwfc: 这题用到鸽笼原理，好高深… 08/04 17:03