Simplest way of explaining Pi is an irrational number

Question

I understand that, an irrational number can't be expressed as a fraction.

Pi is one of those number, that it is an irrational number.

Can someone explain in the simplest way if possible, how to show that pi is an irrational number?

I have read all those proofs but can't seem to understand any of it.

Answer 1

There is a really short proof by I. Niven. You will understand it. It is just one page, and it uses only elementary calculus. I think this is more or less the simplest proof possible.