SOLUTION: A True-False test has 20 questions with each having 2 possible answers with one correct. Assume a student randomly guesses the answer to every question. (2.5 points each)
a. Wha
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a. Wha
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Question 449390: A True-False test has 20 questions with each having 2 possible answers with one correct. Assume a student randomly guesses the answer to every question. (2.5 points each)
a. What is the probability of getting exactly 9 correct answers?
b. What is the probability of getting fewer than 6 correct answers?
You can put this solution on YOUR website! A True-False test has 20 questions with each having 2 possible answers with one correct. Assume a student randomly guesses the answer to every question. (2.5 points each)
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Binomial Problem with n= 20 and p = 1/2
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a. What is the probability of getting exactly 9 correct answers?
P(x = 9) = 20C9(1/2)^20 = 167969/2^20 = 0.1602
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b. What is the probability of getting fewer than 6 correct answers?
P(0<= x <=5) = binomcdf(20,1/2,5) = 0.0207
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Cheers,
Stan H.
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