From Laura K. Lawless,
Your Guide to French Language.

Approximate French Numbers

Estimate and make guesses with approximate French numbers

When you want to make an estimate or take a guess, you can use approximate numbers. Most approximate French numbers are formed with the cardinal number, minus the final e (if any), plus the suffix -aine.

une dizaine about ten (note that x in dix changes to z)

une douzaine a dozen

une quinzaine about fifteen

une vingtaine about twenty

une trentaine about thirty

une quarantaine about forty

une cinquantaine about fifty

une soixantaine about sixty

une centaine about a hundred

un millier about a thousand

Approximate numbers are treated grammatically as expressions of quantity, and like all expressions of quantity, approximate numbers must be joined to the noun they modify with de.

une dizaine d'étudiants about 10 students

une quarantaine de livres about 40 books

des centaines de voitures hundreds of cars

des milliers de documents thousands of documents

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French Translation :: All About Any :: Approximate French Numbers :: Synonyms For Bon :: All About Comme :: French Accent Homographs

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