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rational number

American  

noun

Mathematics.
  1. a number that can be expressed exactly by a ratio of two integers.


rational number British  

noun

  1. any real number of the form a / b , where a and b are integers and b is not zero, as 7 or 7/3

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

rational number Scientific  
  1. A number that can be expressed as an integer or a quotient of integers. For example, 2, −5, and 1/2 are rational numbers.


Etymology

Origin of rational number

First recorded in 1900–05

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

If the two new arrangements contained repeating patterns, the length of their translation vectors should have been related to each other—specifically, their ratio should have been a rational number.

From Scientific American • Apr. 10, 2023

We have also seen that every fraction is a rational number.

From Textbooks • Apr. 22, 2020

A rational number is a number that can be written as a ratio of two integers.

From Textbooks • Apr. 22, 2020

In Table 1.11, we list some rational numbers approaching 2, and the values of 2 x for each rational number x are presented as well.

From Textbooks • Mar. 30, 2016

If we were to throw a dart at the number line, it would never hit a rational number.

From "Zero: The Biography of a Dangerous Idea" by Charles Seife

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