The three digit numbers are $135,153,351,315,513,531$. The numbers that end in 5 are divisible are 5 , and the probability of choosing those numbers is (B) $\frac{1}{3}$. 
A three-digit integer contains one of each of the digits $1,3$ , and $5$ . What is the probability that the integer is divisible by $5$ ? (2009 AMC 8 Problem, Question \#13) 

1. $\frac{1}{6}$ 
2. $\frac{1}{3}$ 
3. $\frac{1}{2}$ 
4. $\frac{2}{3}$ 
5. $\frac{5}{6}$ 