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Director
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In a certain animal population, for each of the first 3 [#permalink]
21 Jan 2005, 08:36
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0% (00:00) correct
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In a certain animal population, for each of the first 3 months of life, the probability that an animal will die during that month is 1/10. For a group of 200 newborn members of the population, approximately how many would be expected to survive the first 3 months of life?
(A) 140
(B) 146
(C) 152
(D) 162
(E) 170
Last edited by qhoc0010 on 21 Jan 2005, 13:18, edited 1 time in total.
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Director
Joined: 31 Aug 2004
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I guess there is a flaw in your proba...
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Senior Manager
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I agree with twixt, how can the probability be 101. The total probability of any event is 1.
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SVP
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I've seen that question. The probability in the question is 10%.
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Director
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Expected value = Prob of survival for 3 months * Number of samples
E(x) = (9/10)*(9/10)*(9/10)*200 = 146
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Director
Joined: 29 Oct 2004
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Got it, thx
OA is (B)
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