A quiz consists of 10 multiple choice questions, each with 5 possible answers. Math?

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ShaneAnderson

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A quiz consists of 10 multiple choice questions, each with 5 possible answers, one of which is correct. to pass the quiz a student must get a 60 percent or better on the quiz. If a student randomly guesses, what is the probability that the student will pass the quiz?
 
I will start you off.
To pass the student has to get 6 or more right.
The probability of getting exactly 6 right is 10C6*p^6*q^4 where p = .2 and q = .8

To pass you need to get exactly 6 right or exactly 7 right or ... etc.
Sum those probabilities and you have the answer.
A bit of work, but I don't see a simpler approach.
 
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