Rational Numbers
Rational numbers are numbers that can be expressed as a ratio of two integers, where the denominator is not zero. They can be written in the form a/b, where a and b are integers and b is not equal to zero.

Types of Rational Numbers
- Positive Rational Numbers: Numbers greater than zero that can be expressed as a ratio of two integers.
- Negative Rational Numbers: Numbers less than zero that can be expressed as a ratio of two integers.
- Zero: Zero is also considered a rational number as it can be expressed as 0/1.

Properties of Rational Numbers
- Closure Property: The sum, difference, product, or quotient of two rational numbers is always a rational number.
- Commutative Property: The order of addition and multiplication does not change the result for rational numbers.
- Associative Property: The grouping of rational numbers in addition and multiplication does not change the result.
- Distributive Property: Multiplication distributes over addition and subtraction for rational numbers.

Operations on Rational Numbers
- Addition: To add two rational numbers, find a common denominator, add the numerators, and simplify if needed.
- Subtraction: To subtract two rational numbers, find a common denominator, subtract the numerators, and simplify if needed.
- Multiplication: To multiply two rational numbers, multiply the numerators together and the denominators together.
- Division: To divide two rational numbers, multiply the first number by the reciprocal of the second number.
Understanding rational numbers is crucial in mathematics as they form the basis for many mathematical operations and concepts.