r*****t
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lhict (至少还有我) 于 (Sat Apr 28 20:22:06 2007) 提到:
A spider eats three flies a day. Until he fills his quota, he has a 50%
chance of catching any fly that attempts to pass his web. What are a fly's
chances of survival, given that five flies have already made the attempt
today?
我的答案是3/4.不知对不对？
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BulletTooth (DesertEagle.50) 于 (Sat Apr 28 20:41:37 2007) 提到:
条件概率啊。
F: flies already eaten by spider today
P(F=3) * 1 + |
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