Basically, a rational number is anything that can be written as a Ratio.
Numbers such as 1/2, 1/3, 0.10.
A rational number is a number that is expressed as the ratio of two integers, where the denominator should not be equal to zero,
Rational numbers include 3/4, 5.6, 5/7
They don't include, 3/0, 4/0, and pi.....
Rational numbers can also be negative. For example, -2/5 is a rational number, because it is expressed as the ratio of -2 to 5.