What is the essence of Pi?
I was thinking about numerical sets and suddenly got confused. We know that Pi is an irrational number. We also know that Pi is the ratio of the circumference of a circle to its diameter. That is, we are essentially dividing two numbers. And here it became unclear to me: where do we get the irrationality of Pi, if when dividing rational numbers, we should always get a rational number. It turns out that the length of a circle and its diameter are always irrational numbers? But in this case, how could we get such an exact value of Pi, if with the irrationality of the diameter and length, we could never calculate this value so accurately?