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
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truplayer256
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Note that for each month of life, the animal population has a 90% chance of living. Therefore, the number of animals expected to survive the first 3 months of life is:
200(0.9)^3 = 200(81*9)/(1000) = (81*9)/5 => ((80 + 1)*9)/5
= 144 + 9/5 = 145.8
About 146
Choose B.
200(0.9)^3 = 200(81*9)/(1000) = (81*9)/5 => ((80 + 1)*9)/5
= 144 + 9/5 = 145.8
About 146
Choose B.
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Anurag@Gurome
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Probability of survival for each of the first 3 months of life = 1 - 1/10 = 9/10grandh01 wrote: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
So, from a group of 200 newborn members of the population, number expected to survive the first 3 months of life = 200 * 9/10 * 9/10 * 9/10 = 146 approx.
The correct answer is B.
Anurag Mairal, Ph.D., MBA
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