ENGLISH
REFERENCE

ratio

n. countable
C1 Advanced Oxford US //ˈɹeɪʃiˌoʊ// UK //ɹˈeɪʃɪˌəʊ// ra·tio Academic

n. the relationship between two amounts, showing how many times one value contains or is contained within the other. You use it to compare the sizes of two groups or numbers.

n. the quantitative relation between two amounts showing the number of times one value contains or is contained within the other. Often expressed as two numbers separated by a colon.


SIMPLE

The ratio of boys to girls in the class is two to one.

CONTEXTUAL

The school maintains a low student-to-teacher ratio to ensure every child receives individual attention.

COMPLEX

Financial analysts examine the debt-to-equity ratio to determine whether a company is over-leveraged and at risk of insolvency during a market downturn.

Synonyms
Origin

Borrowed from Latin ratiō. Doublet of ration and reason.

Usage

Commonly follows the pattern 'the ratio of A to B'.

Pitfall

the ratio between boys and girlsthe ratio of boys to girlsWhile 'between' is sometimes used, 'of... to...' is the standard mathematical and academic construction.

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