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:

C_k(n) = {n choose k} = frac{ n! }{ k! (n-k)!} $ $ C_{{ 3}}(11) = {{ 11} choose 3} = frac{ 11! }{ 3!(11-3)!} = frac{ 11 * 10 * 9 } { 3 * 2 * 1 } = 165 $ $

Number of combinations: 165