SOLUTION: You are taking a true-false test that has ten question, and you need a score of 70 percent to pass. You know the answers to only six of the questions. For the other four, you toss

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Question 765100: You are taking a true-false test that has ten question, and you need a score of 70 percent to pass. You know the answers to only six of the questions. For the other four, you toss a coin and answer true if it comes up heads and false if it comes up tails.
What is the probability that you will pass the exam? (Think about this as the probability of getting at least one right answer in four tries-or one minus the probability of getting four wrong answers.)
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
You are taking a true-false test that has ten question, and you need a score of 70 percent to pass. You know the answers to only six of the questions. For the other four, you toss a coin and answer true if it comes up heads and false if it comes up tails.
What is the probability that you will pass the exam?
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Ans:
P(quessing correctly) = 1/2
P(flipping correctly)= 1/2
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P(pass) = 1/4
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Cheers,
Stan H.
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