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How to Express a Rational Number As the Ratio of Two Integers

A subset of real numbers, integers are composed of the natural numbers, or numbers greater than or equal to zero, and negative numbers. An integer must also be a number that can be expressed without a decimal or fractional component. Examples of integers include 1, -3, 100 and -5. Rational numbers can be written as ratios of two integers and include all fractions not having a zero denominator. You can express decimal numbers, especially repeating decimals, as the ratio of two integers to provide less complex and more easily interpreted values. Thus, being able to write rational numbers as ratios is a useful tool applicable in all levels of mathematics.

Instructions

- 1
  Write any whole, rational, number as a fraction over a denominator of one. Any rational number that does not contain a decimal component may be expressed as the ratio of two integers using 1 as the denominator. For example, 2 may also be written as 2/1 and 5 as 5/1.
- 2
  Determine the last decimal place if the number is not a whole number. The last placeholder will indicate the bottom integer on the ratio. For example, the last placeholder in the decimal 0.15 is in the hundredths position.
- 3
  Remove the decimal point and write the number as the numerator of the ratio with the denominator as the value determined in Step 2. Therefore, the decimal would be written as a ratio in the form of 15/100.
- 4
  Reduce the ratio if possible. The numerator and denominator of 15/100 have a greatest common factor of 5. Dividing each number by the value reduces the fraction to 3/20. Thus, the rational number 0.15 is written as the ratio of two integers in the form of 3/20.

Definition of Binomial Factors

How to Write the Remainder As a Whole Number