what is a rational number

A rational number is a number that can be expressed as the quotient or fraction of two integers, where the denominator is not zero. For example, 3/4, -5/2, and 7/1 are all rational numbers. Every integer is also a rational number, as it can be expressed as a fraction with a denominator of 1. The set of all rational numbers is usually denoted by boldface Q or blackboard bold. Rational numbers can be represented as terminating decimals or repeating decimals. For example, 0.75 and 0.20454545... are rational numbers. However, numbers like the square root of 2 and pi are not rational numbers and are called irrational numbers.