# Statistics - Factorial

Factorial is a function applied to natural numbers greater than zero. The symbol for the factorial function is an exclamation mark after a number, like this: 2!

## Formula

${n! = 1 \times 2 \times 3 ... \times n}$

Where −

• ${n!}$ = represents factorial

• ${n}$ = Number of sets

### Example

Problem Statement:

Calculate the factorial of 5 i.e. 5!.

Solution:

Multiply all the whole numbers up to the number considered.

${5! = 5 \times 4 \times 3 \times 2 \times 1 , \\[7pt] \, = 120}$