SOLUTION: A Finite final consists of 30 multiple choice questions. If each question has 4 choices and 1 right answer, find the probability that a student gets an A (i.e. 27 or better) by pur
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Question 1191245: A Finite final consists of 30 multiple choice questions. If each question has 4 choices and 1 right answer, find the probability that a student gets an A (i.e. 27 or better) by purely guessing on each question. Answer by ikleyn(52821) (Show Source):
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A Finite final consists of 30 multiple choice questions.
If each question has 4 choices and 1 right answer, find the probability
that a student gets an A (i.e. 27 or better) by purely guessing on each question.
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For each individual multiple choice question of 30 multiple questions,
the probability to guess correctly is = 0.25;
the probability to guess incorrectly is = 0.75.
Next, P = P(27) + P(28) + P(29) + P(30) = use the formulas for the binomial distribution =
= + + + =
= 9.50802*10^(-14) + 3.39572*10^(-15) + 7.80626*10^(-17) + 8.67362*10^(-19) = 9.85548*10^(-14). ANSWER
