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? 
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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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