How many ways can you put 5 different letters in order?

Answer 1

Let's start with the first.

You have 5 to choose from so that's 5.

Now for each of those 5, let's choose the second letter.

You now have 4 to choose from.

So we're up to 5 x 4.

In the third position we're down to a choice of 3, so total possibilities go up to 5x4x3.

In the fourth, we have 2 left, so the choices go up to 5x4x3x2.

After all that, there is only one left for the fifth position: just one to choose from.

So the final answer: 5x4x3x2x1.

That's called 5 factorial.