SOLUTION: A student takes an exam containing 14 true or false questions. If the student guesses, what is the probability that he gets less than 6 but more than 3 questions right?

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Question 911288: A student takes an exam containing 14 true or false questions. If the student guesses, what is the probability that he gets less than 6 but more than 3 questions right?
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
p = .5, n = 14
P(3< x <6) = binomcdf(14, .5, 6) - binomcdf(14,.5,3)
These are Instructions for the use of the TI Calculator
Strongly Recommend having one and knowing how to use the statistic functions
on it.
Another backup to check You had calculated probabilities can be found on stattrek.com
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By hand this would be:
Using P+%28x%29=+highlight_green%28nCx%29%28p%5Ex%29%28q%29%5E%28n-x%29+
p and q are the probabilities of success and failure respectively.
In this case p & q are = 1/2 or .5, n = 14
nCx+=+%28n%21%29%2Fx%21%28n+-+x%29%21%29
P(4 0r 5 correct) = 14C4(.5)^4(.5)^10 + 14C5(.5)^5(.5)^9
P(4 0r 5 correct) = 1001(.5)^4(.5)^10 + 2002(.5)^5(.5)^9