 # 15 Permutations of 8

## Enter your n and r values below:

<-- Enter (n)
<-- Enter (r)

Evaluate the following permutation
15P8

## Permutation Definition:

An order or arrangement

## Permutation Formula:

 nPr  = n! (n - r)!

where n is the number of items
r is the number of arrangements.

## Plug in n = 15 and r = 8

 15P8  2 15! (15 - 8)!

## Factorial Formula:

n! = n * (n - 1) * (n - 2) * .... * 2 * 1

## Calculate n!:

n! = 15!
15! = 15 x 14 x 13 x 12 x 11 x 10 x 9 x 8 x 7 x 6 x 5 x 4 x 3 x 2 x 1
15! = 1,307,674,368,000

## Calculate (n - r)!:

(n - r)! = (15 - 8)!
(15 - 8)! = 7!
7! = 7 x 6 x 5 x 4 x 3 x 2 x 1
7! = 5,040

## Calculate 15P8:

 15P8  = 1,307,674,368,000 5,040

## Excel or Google Sheets formula:

=PERMUT(15,8)

15P8 = 259,459,200

### How does the Permutations and Combinations Calculator work?

Free Permutations and Combinations Calculator - Calculates the following:
Number of permutation(s) of n items arranged in r ways = nPr
Number of combination(s) of n items arranged in r unique ways = nCr including subsets of sets
This calculator has 2 inputs.

### What 2 formulas are used for the Permutations and Combinations Calculator?

1. nPr=n!/r!
2. nCr=n!/r!(n-r)!

For more math formulas, check out our Formula Dossier

### What 4 concepts are covered in the Permutations and Combinations Calculator?

combination
a mathematical technique that determines the number of possible arrangements in a collection of items where the order of the selection does not matter
nPr = n!/r!(n - r)!
factorial
The product of an integer and all the integers below it
permutation
a way in which a set or number of things can be ordered or arranged.
nPr = n!/(n - r)!
permutations and combinations