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Writing Numbers with Fractions and Fractions in Full
Hyphens with Whole Numbers and Numbers with Fractions
Here are the rules for using hyphens with whole numbers and numbers that include fractions.

Do Not Use Hyphens with Numbers Used as Quantifiers
When the number is a quantifier to a noun, do not use a hyphen. In these examples, the numbers are highlighted and the nouns are in bold.- The journey takes two hours.
- The journey takes two and a half hours.
- The journey takes twenty-three and a quarter hours. (In this example, "twenty-three" is hyphenated because that's how 23 is written in full.)
- The journey takes 23.25 hours.
- The journey takes one and three-quarter hours. (Here, "three-quarter" is hyphenated because that's how a fraction is written in full.)
Use Hyphens with Numbers Used in Adjectives
When the number is the first part of a compound adjective, use hyphens to group the whole adjective together to show it is a single adjective. In these examples, the compound adjectives that include the numbers are highlighted and the nouns are in bold.- It is a two-hour journey.
- It is a two-and-a-half-hour journey.
- It is a twenty-three-and-a-quarter-hour journey.
- It is a 23.25-hour journey.
- It is a one-and-three-quarter-hour journey.
Read more about compound adjectives.
Hyphenating Terms with the Word "Year"
Writers often ask about hyphenation with terms that include "year." Here are the rules:Hyphenate All the Words in a Compound Noun with Years
The term "two-year-old" is a multi-word noun (called a compound noun.) Here are some more examples of compound nouns with the term "year old" (the compound nouns are highlighted).- A two-year-old knows its mind.
- There are three two-year-olds in the group.
- A four-and-a-half-year-old knows its mind.
- There are three four-and-a-half-year-olds in the group.
- He claims to have seen a six-and-a-half-footer near the breakwater.
- She studied for four years.
- She studied for four and a half years.
- She studied for a four-year period.
- She studied for a four-and-a-half-year period.
Writing Fractions in Words

- The population reduced by two-fifths. (This is how ⅖ is written.)
- The population reduced by one-half. (This is how ½ is written.)
- The population reduced by 3 and one-third. (This is how 3⅓ is written.)
- I will receive three thirty-fifths of my salary. (This is how 3/35 is written. "Three-thirty-fifths" looks too unwieldy.)
- I will receive forty-one fiftieths of my salary. (This is how 41/50 is written. "Forty-one-fiftieths" looks too unwieldy.)
- I will receive forty-fiftieths of my salary. (This is how 40/50 is written. If there are no hyphens in the numerator or the denominator, then revert to the normal rules.)
Hyphenation with Fractions as Quantifiers
Another popular style differentiates between standalone fractions and fractions used as quantifiers. In this style, a fraction is not hyphenated when it stands alone but is hyphenated when it is used as a quantifier. For example:- The population reduced by two fifths. (Note that this is different from the most common style shown above.)
- There was a two-fifths reduction in the population. (In this example, "two-fifths" is hyphenated because it quantifies "reduction.")
Interactive Exercise
Here are three randomly selected questions from a larger exercise, which can be edited, printed to create an exercise worksheet, or sent via email to friends or students.- Do you disagree with something on this page?
- Did you spot a typo?