Quotient

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12 apples divided into 4 groups of 3 each.
The quotient of 12 apples by 3 apples is 4.

In arithmetic, a quotient (from Latin: quotiens "how many times", pronounced /ˈkwʃənt/) is a quantity produced by the division of two numbers.[1] The quotient has widespread use throughout mathematics, and is commonly referred to as the integer part of a division (in the case of Euclidean division),[2][3] or as a fraction or a ratio (in the case of proper division). For example, when dividing 20 (the dividend) by 3 (the divisor), the quotient is 6 in the Euclidean division sense, and in the proper division sense. In the second sense, a quotient is simply the ratio of a dividend to its divisor.

Notation[edit]

The quotient is most frequently encountered as two numbers, or two variables, divided by a horizontal line. The words "dividend" and "divisor" refer to each individual part, while the word "quotient" refers to the whole.

Integer part definition[edit]

The quotient is also less commonly defined as the greatest whole number of times a divisor may be subtracted from a dividend—before making the remainder negative. For example, the divisor 3 may be subtracted up to 6 times from the dividend 20, before the remainder becomes negative:

20 − 3 − 3 − 3 − 3 − 3 − 3 ≥ 0,

while

20 − 3 − 3 − 3 − 3 − 3 − 3 − 3 < 0.

In this sense, a quotient is the integer part of the ratio of two numbers.[4]

Quotient of two integers[edit]

A rational number can be defined as the quotient of two integers (as long as the denominator is non-zero).

A more detailed definition goes as follows:[5]

A real number r is rational, if and only if it can be expressed as a quotient of two integers with a nonzero denominator. A real number that is not rational is irrational.

Or more formally:

Given a real number r, r is rational if and only if there exists integers a and b such that and .

The existence of irrational numbers—numbers that are not a quotient of two integers—was first discovered in geometry, in such things as the ratio of the diagonal to the side in a square.[6]

More general quotients[edit]

Outside of arithmetic, many branches of mathematics have borrowed the word "quotient" to describe structures built by breaking larger structures into pieces. Given a set with an equivalence relation defined on it, a "quotient set" may be created which contains those equivalence classes as elements. A quotient group may be formed by breaking a group into a number of similar cosets, while a quotient space may be formed in a similar process by breaking a vector space into a number of similar linear subspaces.

See also[edit]

References[edit]

  1. ^ "Quotient". Dictionary.com.
  2. ^ "The Definitive Higher Math Guide to Long Division and Its Variants for Integers (Euclidean Division — Terminology)". Math Vault. 2019-02-24. Retrieved 2020-08-27.
  3. ^ Weisstein, Eric W. "Integer Division". mathworld.wolfram.com. Retrieved 2020-08-27.
  4. ^ Weisstein, Eric W. "Quotient". MathWorld.
  5. ^ Epp, Susanna S. (2011-01-01). Discrete mathematics with applications. Brooks/Cole. p. 163. ISBN 9780495391326. OCLC 970542319.
  6. ^ "Irrationality of the square root of 2". www.math.utah.edu. Retrieved 2020-08-27.