Question 128589
Each question of a 5-question multiple choice exam has 3 possible answers.  Suppose a student picks an answer at random for each question.  Find the probability the student selects the correct answer on none of the questions. 
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Prob he gets a particular question wrong is (2/3).
Prob he gets all 5 questions wrong is (2/3)^5 = 0.1317
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Cheers,
Stan H.