Foundation
Mathematics Foundation
Properties of Real Number
Irrational Number
Properties of Circle
Question

Recall, π is defined as the ratio of the circumference(say c) of a circle to its diameter(say d). That is, π=cd. This seems to contradict the fact that π is irrational. How will you resolve this contradiction?

JEE Advance
College PredictorLive

Know your College Admission Chances Based on your Rank/Percentile, Category and Home State.

Get your JEE Main Personalised Report with Top Predicted Colleges in JoSA

Solution
Verified BY
Verified by Zigyan

Here, 

π=227
Now, it is in the form of pq, which is a rational number, but this is an approximate value of π.
If you divide 22 by 7, the quotient (3.14⋯ ) is a non-terminating number i.e. it is irrational.
Approximate fractions include (in order of increasing accuracy)
227,333106,355113,
If we divide anyone of these we get, the quotient (3.14⋯ ) is a non-terminating number. i.e. it is irrational.
So,
There is no contradiction as either c or d irrational and 
hence π is a irrational number.