Explain how you can determine whether or not a number is rational

The easiest way to tell if a number is rational or not is to attempt to express it as a fraction. If you can, then the number is rational. If not, then the number is irrational. All integers are rational numbers, because they can be written as a fraction (for example, the integer 8 = 8/1). But numbers like pi or sqrt(2) cannot be written as a fraction and are not rational.