SOLUTION: In a fifteen question true false examination a student must acheive five correct answers to pass. If student answer randomly what is the probability that student will fail?

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Question 429911: In a fifteen question true false examination a student must acheive five correct answers to pass. If student answer randomly what is the probability that student will fail?
Answer by ewatrrr(24785) About Me  (Show Source):
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Hi

Note: The probability of x successes in n trials is: 

P = nCx* p%5Ex%2Aq%5E%28n-x%29 where p and q are the probabilities of success and failure respectively. 

In this case p & q are = 1/2 or .5

nCx = n%21%2F%28x%21%28n-x%29%21%29

P( less than 5 correct) = P(4correct)+ P(3)+  P(two)+  P(one)+  P(none)

                          0.041660 +.013890 + .003200 + .000460 + .000030

P( less than 5 correct)= .05923