TITLE: probability of being dealt four of a kind in poker
QUESTION [5 upvotes]: I have to resolve this exercise:
I have 52 cards. I get 5 cards. Calculate the probability I get a poker hand of four-of-a-kind.
well I applied  the formula ${52 \choose 5}=\frac{52!}{5!47!}$ to calculate every possible combination.but after here I don't know how can go ahead. Some help?
Edit
I made mistake.Now it's correct

REPLY [3 votes]: Hint:  Your formula is the total number of $5$ card hands.  How many choices of rank of the four are there?  How many choices for the other card?