You rent a 5-passenger car so you can go to the grand canyon with 4 friends

How many different ways people can sit? (Suppose that anybody could drive )

You could get the answer by doing this math.

5 × 4 × 3 × 2 × 1

= 20 × 3 × 2 × 1

= 60 × 2 × 1

= 120 × 1

= 120

If you enter 5 in the box, you will see that the answer is 120

Thereofore, there are 120 ways you and your friends can sit.

You are going to plant 7 trees on your back yard

How many different ways can this task be done?

You could get the answer by doing this math.

7 × 6 × 5 × 4 × 3 × 2 × 1

= 42 × 5 × 4 × 3 × 2 × 1

= 210 × 4 × 3 × 2 × 1

= 840 × 3 × 2 × 1

= 2520 × 2 × 1

= 5040 × 1

= 5040

If you enter 7 in the box, you will see that the answer is 5040

Thereofore, there are 5040 ways to plant 7 trees.

Just enter only one number in the big box and hit the button that says "

As you can see, this calculator will become very useful when the number is big. Not many people want to get the factorial of 25 with paper and pencil

How will you get the factorial of x. The factorial calculator is not built to handle that.

Note that x! = x × (x - 1)× (x - 2) × (x - 3) ..... × 1