作者jackoyu (伟下列资料正确填写并回숩
看板Grad-ProbAsk
标题[商管] [统计]-逢甲94-统计与精算-古典机率
时间Tue Dec 1 16:33:54 2009
Suppose there are 5 color balls in each of the three urns A1,A2,A3 for which
contains 1,2,3 red balls, respectively. We draw a ball at random from A1 to
A2, and then draw a ball at random from A2 to A3.
a) A ball is then drawn at random from A3, find the probability that the ball
is red.
b) One urn is then chosen at random and one ball is drawn from it also at
random. If the ball is red, what is the probability that the chosen urn
was A3?
请各位帮个忙，谢谢!!
感激不尽!!
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