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How is $\pi$ actually defined? If it is defined as the ratio of the circumference of a circle to its diameter then from this definition itself either of the circumference and diameter has to be irrational. The circumference and diameter both are finite but $\pi$ is irrational. An irrational number is a number with never ending numbers after decimal, till now no recurrence has been discovered.
Yet there are methods to represent them in a number line which means they have finite length. So, if we take a finite length and make a circle around it as diameter, does it mean circumference is irrational but finite? In our everyday life, do we always take rounded off values of circumference or diameter?