SOLUTION: A statistics textbook chapter contains 66 exercises, 12 of which are essay questions. A student is assigned 16 problems. What is the probability that at least one is essay?

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Question 841689: A statistics textbook chapter contains 66 exercises, 12 of which are essay questions. A student is assigned 16 problems. What is the probability that at least one is essay?

Found 2 solutions by stanbon, reviewermath:
Answer by stanbon(75887) (Show Source):
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A statistics textbook chapter contains 66 exercises, 12 of which are essay questions. A student is assigned 16 problems. What is the probability that at least one is essay?
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Binomial Problem with n = 16 and p(essay) = 12/66 = 2/11
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P(at least one) = 1 - P(none are essay)
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= 1 - (9/11)^16
= 1 - 0.0403
= 0.9597
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Cheers,
Stan H.
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Answer by reviewermath(1029) (Show Source):
You can put this solution on YOUR website!
Q:
A statistics textbook chapter contains 66 exercises, 12 of which are essay questions. A student is assigned 16 problems. What is the probability that at least one is essay?
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A:
If we use Binomial Distribution, we only get an approximate answer since the probability of success (the event of answering an essay question) is different from trial to trial.
We use Hypergeometric Distribution to get the exact answer.
P(none are essay) = = 0.02466
Therefore, P(at least one essay) = 1 - 0.02466 =