Question 776359
College student has learned 35 questions out of 40 questions.
On the test he gets 3 questions.
What's the probability that he passes the exam if he needs to answer 
at least 2 questions on the test.
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# of ways to succeed::: 35C2*5C1+ 35C3*5C0 = 9520
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# of possible outcomes:::  40C3 = 9880
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P(at least 2 correct) = 9520/9880 = 0.9636
Cheers,
Stan H.
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