# Math Help - probability problem

1. ## probability problem

A room contains twelve people who are wearing badges numbered 1 to 12. If three people are randomly selected, what is the probability that the person wearing badge 6 will be included?

I did 1/(12C3) and got 1/55. I'm not sure if I did it right =O

2. $\frac {{11 \choose 2}} {{12 \choose 3}} = \frac {1}{4}$
WHY?

3. Since I am only looking for the chance badge 6 will be included, it is one choice out of choosing 3 from a total of 12. Is it incorrect? O.O What is it supposed to be?