# Permutations

by
**nicolealvarezcc**

Last updated 7 years ago

** Discipline: **

Math ** Subject: **

Pre-Calculus
** Grade:**

10

An ordering of n objects is a permutation of the objects. Example: there are six permutations of the letter A, B, and C:ABC ACB BAC BCA CAB CBAYou can use the fundamental counting principle to find the number of permutations of A, B, and C. There are 3 choices for the first letter. After the first has been chosen, 2 choices remain for the second letter. Finally, after the first two letters have been chosen, there is only 1 choice remaining for the final letter. So, the number of permutations is 3 x 2 x 1 = 6 The expression 3 x 2 x 1 can also be written as 3! in which ! is the factorial symbol. In general, n! is defined where n is a positive integer, example:n! = n x (n-1) x (n-2) x ... x 3 x 2 x 1

Permutations

Nicole Alvarez del C.

VIDEO...

Example:

In conlclusion, permutations can help us to find how many possible answers there are to a certain problem. It can help us to to calculate odds in games of chance, in molecular chemistry, etc.

## alaa87 7 years ago

nice

## alaa87 7 years ago

nice