Question

How do you tell the difference between rational and irrational numbers?

Answer 1

Rational numbers have are wither self terminating, or if they are non terminating, then they have a pattern.
Irrational numbers are non terminating and have no pattern.

Answer 2

a rational number is a number that can be written in a ratio of two integers. ex: 8 is rational because it can be written as 8/1, .001 is rational because it can be written as 1/1000.
an irrational number cannot be expressed as a ratio. ex: the number pi (3.145.....) is is not a simple fraction
hope it helps :)