SOLUTION: Van guessed on all 8 questions of a multiple-choice quiz. Each question has 4 answer choices. What is the probability that he got exactly 1 question correct? Round the answer to th

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Question 1035210: Van guessed on all 8 questions of a multiple-choice quiz. Each question has 4 answer choices. What is the probability that he got exactly 1 question correct? Round the answer to the nearest thousandth.

Answer by rothauserc(4718) About Me  (Show Source):
You can put this solution on YOUR website!
We use the binomial probability formula to solve this problem
:
p=1/4, q=3/4 and n=8
:
Pr(guessing 1 question correctly) = 8C1 * (1/4)^1 * (3/4)^(8-1) = 0.266967 approx 0.267
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Note that 8C1 = 8! / 1! * (8-1)! = 8
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Probability of guessing 1 question correctly is 0.267
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