# GCSE Statistic - Factorials

- Created by: YellowYeti
- Created on: 18-06-12 09:42

Fullscreen

**What is a factorial?**

- A factorial shows us how many possibilities there are for a situation
- For n items, there are n! possibilities, therefore n! means we multiply all of the numbers from n, to one.

For example: 6!

n = 6, so...

6! = 1 x 2 x 3 x 4 x 5 x 6 = 720 different possibilities.

Another example: 4! = 1 x 2 x 3 x 4 = 24 different possibilities.

**Example (taken from MyMaths):**

6 pupils are lined up for a photo. What is the propability that the tallest pupil is at one end, and the shortest is at the other end?

- First, find out how many possibilities there are for this situation.
- There are 6 students, so we have to work out 6! : 6! = 1 x 2 x 3 x 4 x 5 x 6 =…

## Comments

No comments have yet been made