SOLUTION: A student is preparing for an upcoming midterm exam. The professor given the student 40 practice questions and plans to select 12 of the questions at random to create the midterm e

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Question 1000158: A student is preparing for an upcoming midterm exam. The professor given the student 40 practice questions and plans to select 12 of the questions at random to create the midterm exam. Suppose the student knows how to correctly answer 34 of the 40 questions. Let X represent the number of questions the student answers correctly on the exam.
What is the probability distribution of X?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
A student is preparing for an upcoming midterm exam. The professor given the student 40 practice questions and plans to select 12 of the questions at random to create the midterm exam. Suppose the student knows how to correctly answer 34 of the 40 questions. Let X represent the number of questions the student answers correctly on the exam.
What is the probability distribution of X?
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mean = n*p = 12*(34/40)
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std = sqrt(npq) = sqrt[12*(34/40)*(6/40)]
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Cheers,
Stan H.
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