9 Choose 1
Combination Calculator
What is 9 choose 1?
Answer
9 choose 1 is
9
Order doesn't matter, no repeats: 9 ways to choose 1 of 9 items.
C(9, 1) = 9! / (1! · 8!)
= 9 / 1
= 9
Row sum: 29 = 512 — all subsets of 9 items.
See Also
- Random Number Generator - Pick a random whole number between two bounds
- Percent to Probability Converter - Convert Percents to "1 in X" Probability Chance
- Factors of a Number - List all Factors and Factor Pairs of a Number
n choose 1 for other n
FAQ
What is 9 choose 1?
9 choose 1 is 9
Why is 9 choose 1 the same as 9 choose 8?
Every way to choose 1 of 9 items leaves exactly 8 behind, so choosing 1 and choosing which 8 to leave out are the same count: 9 choose 1 = 9 choose 8 = 9. In the formula n! / (k! (n − k)!) the two factorials below just swap places.
How many ways are there if order matters?
The same 9: with 1 chosen item there is only one order, so P(9, 1) = 9 choose 1 = 9. Order starts to matter from 2 items on: n × (n − 1) arrangements.
See Also
- 8 Choose 0: Combinations C(8, 0)
- 8 Choose 1: Combinations C(8, 1)
- 8 Choose 2: Combinations C(8, 2)
- 8 Choose 3: Combinations C(8, 3)
- 8 Choose 4: Combinations C(8, 4)
- 8 Choose 5: Combinations C(8, 5)
- 8 Choose 6: Combinations C(8, 6)
- 8 Choose 7: Combinations C(8, 7)
- 8 Choose 8: Combinations C(8, 8)
- 9 Choose 0: Combinations C(9, 0)
- 9 Choose 2: Combinations C(9, 2)
- 9 Choose 3: Combinations C(9, 3)
- 9 Choose 4: Combinations C(9, 4)
- 9 Choose 5: Combinations C(9, 5)
- 9 Choose 6: Combinations C(9, 6)
- 9 Choose 7: Combinations C(9, 7)
- 9 Choose 8: Combinations C(9, 8)
- 9 Choose 9: Combinations C(9, 9)
- 10 Choose 0: Combinations C(10, 0)
- 10 Choose 1: Combinations C(10, 1)
- Число сочетаний из 9 по 1
- Combinaciones de 9 tomados de 1 en 1: C(9, 1)
- Combinação de 9 tomados 1 a 1: C(9, 1)