SOLUTION: A multiple choice test consists of 8 items each with 4 choices. A student guesses the answers by choosing an answer at random. Compute the probability that (a) the student answe

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Question 1100742: A multiple choice test consists of 8 items each with 4 choices. A student guesses the answers by choosing an answer at random. Compute the probability that
(a) the student answers all questions incorrectly?
(b) the student answers all questions correctly?
(c) the student answers 2 or more correctly?
(d) Suppose the student is able to eliminate one of the answers as incorrect and chooses randomly from the other three choices. What is the probability the student answers 2 or more correctly?
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
P%28X%29=C%288%2CX%29%2A%280.25%29%5EX%2A%281-0.25%29%5E%288-X%29
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a) P%280%29=0.1001
b) P%288%29=0.0000153
c) P=P%282%29%2BP%283%29%2BP%284%29%2BP%285%29%2BP%286%29%2BP%287%29%2BP%288%29=0.6329
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P%28X%29=C%288%2CX%29%2A%281%2F3%29%5EX%2A%281-1%2F3%29%5E%288-X%29
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d) P=P%282%29%2BP%283%29%2BP%284%29%2BP%285%29%2BP%286%29%2BP%287%29%2BP%288%29=0.8049