Question

Which one is irrational π or 3.14

Answer 1

pi is irrational.

Note: 3.14 is only an approximation for pi, but as it can be expressed as 314/1000, or 157/500, we could call it rational. Moot point.

When you want accuracy, use pi to four or five decimal places. When you want an approximate answer, use 3.14 as a substitute for pi.

Answer 2

An irrational number is one that cannot be shown as ratio of two integers, an 3.14=314/100 so that means pi is irrational. Another thing to note is that pi is transcendental which means it is not the root of any algebraic equation.