Learn the history and rules of spelling 40 as forty, not fourty, and how to use it in sentences. Find out why you need to hyphenate compound numbers after forty and see examples of forty usage. The difference between forty and fourty is simple: forty is correct, and fourty is a common misspelling. In English, the correct way to spell the number 40 is with the letters “ forty .” Despite how it sounds or what logic might suggest (since “four” is part of “ forty ”), adding a “u” as in “fourty” is incorrect. Let’s explore how to write 40 in words, rules for spelling, and real-life uses. A 40 in words simply means how to express the number 40 as an English word. The correct spelling in English is forty (not “fourty”).
