作者passers (路人)
看板Statistics
标题[问题] 可以问翻译吗...
时间Sun Nov 12 14:10:22 2006
For a group of 100 people, compute
(a) the expected number of days of the year
that are birthdays of exactly 3 people:
(b) the expected number of distinct birthdays.
(a)是问说三个人在同一天生日的期望值吗?
(b)应该是一百个人生日都不同天的期望值吧?
(b)expection = 100 * (1 * 364 * 363 * ... * 266) ?
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365 365 365
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