Answer: 0.02734375
Explanation:
Here, the total observation r trials, n = 10
Selected outcomes, r = 5
The probability of getting a right answer, p =

Since, the probability of not getting a right answer, q = 1 - p = 1- 0.5 = 0.5
Thus, By the binomial model,
The probability that of getting r outcomes in the n observation,

Thus, The probability that the student gets 5 out of the 10 questions right,
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