Combinations without repetition

Find out how many different ways you can choose k items from n items set. With/without repetition, with/without order.

(n)
(k)

Calculation:

Ck(n)=(nk)=n!k!(nk)!  n=11 k=3  C3(11)=(113)=11!3!(113)!=11109321=165

Number of combinations: 165