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How to Divide Rational Numbers

A rational number is any number that can be expressed as a fraction. A fraction is a number that is used to represent a part of something. For example, a piece of pie is a fraction of a pie. If you have 5 slices of pie, one slice is 1/5 of the pie. The number on top of a fraction is called the numerator. The number on the bottom of a fraction is called the denominator. Rational numbers never have zero as the denominator. Once you learn how to divide fractions, you can divide rational numbers.

Instructions

- 1
  Write an equation with the rational numbers represented as fractions. For example,
  
  2/4 ÷ 2/3 =
- 2
  Find the reciprocal of the second rational number by reversing the numerator and the denominator. For example, the reciprocal of 2/3 is 3/2.
- 3
  Multiply the first fraction by the reciprocal of the second fraction. For example,
  
  2/4 x 3/2 = 6/8
- 4
  Reduce the final fraction to the lowest common denominator by dividing the numerator and denominator by the greatest common factor. For example, the greatest common factor of 6/8 is 2, so 6 ÷ 2/8 ÷ 2 = 3/4.

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