11 Choose 8

Combination Calculator
Total items (n)
Items chosen (k)

What is 11 choose 8?

Answer

11 choose 8 is
165

Order doesn't matter, no repeats: 165 ways to choose 8 of 11 items.

Choosing 8 of 11 is the same as leaving 3 out: C(11, 8) = C(11, 3).

C(11, 8) = 11! / (8! · 3!)

= C(11, 3)

= (11 × 10 × 9) / (3 × 2 × 1)
= 990 / 6

= 165

If order matters (permutations): P(11, 8) = 11 × 10 × 9 × … × 4 = 6,652,800 — each combination in 8! = 40,320 orders.

Row 11 of Pascal's triangle
k11 choose k
01
111
255
3165
4330
5462
6462
7330
8165
955
1011
111

Row sum: 211 = 2,048 — all subsets of 11 items.

See Also

FAQ

What is 11 choose 8?

11 choose 8 is 165

Why is 11 choose 8 the same as 11 choose 3?

Every way to choose 8 of 11 items leaves exactly 3 behind, so choosing 8 and choosing which 3 to leave out are the same count: 11 choose 8 = 11 choose 3 = 165. In the formula n! / (k! (n − k)!) the two factorials below just swap places.

How many ways are there if order matters?

P(11, 8) = 6,652,800. Each of the 165 combinations can be put in order in 8! = 40,320 ways, so permutations = combinations × k!: P(n, k) = n! / (n − k)!.