Recall, is defined as the ratio of the circumference (say c) of a circle to its diameter (say d).

That is, . This seems to contradict the fact that is irrational. How will you resolve this contradiction?

**Answer:**

There is no contradiction. When we measure any length with ruler or any other device, we only get an approximate rational value. We never get an exact value. So, c or d is irrational when we are actually writing approximate rational values of c and d. So, the fraction is irrational.