Hi,
p = .08,  n = 13
using TI Calculator
P(x=3) = The syntax is binompdf(n, p, x-value)= binompdf(13, .08,3)
Or
 P =  (.08)^3(.92)^10
(.08)^3(.92)^10  
Note: The probability of x successes in n trials is: 
P (x)=  (p)^x(q)^(n-x) where p and q are the probabilities of success and failure respectively.
 (p)^x(q)^(n-x) where p and q are the probabilities of success and failure respectively. 
In this case p = .08 & q  = .92
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