Writing out numbers is a standard rule in research papers and academic texts. Numbers can be written in two main styles – words or numerals – depending on the context and the guidelines set out in the chosen style guide, such as APA, MLA or Chicago. It is important to choose one style and apply it consistently throughout a paper.
Writing numbers below 10 as words is considered standard. For example, one, two, three, etc. There are some exceptions. Numbers that begin a sentence should be written out as words rather than using numerals. For example: “Eight students attended the workshop.” Numbers that identify parts such as examples or pages should also use words (e.g. “See example four.” or “Refer to page six.”).
Beyond 10, the general rule is to use numerals for numbers. There are still instances where words may be preferred. If two or more numbers appear together in a sentence, it is considered clearer to write them out as words for comprehension (e.g.”The survey involved eleven participants between the ages of twenty-three and thirty-two”). Another instance that calls for writing out numbers as words rather than using numerals is when describing precise measurements where clarity is important (e.g. ‘four and one-quarter inches’ versus ‘4 1⁄4 inches’).
Ranges also present a choice between words and numerals. The general rule is to write out any number below 100 as words, and use numerals for triple digit or larger numbers. Therefore a range like ‘between fifty-five and seventy-eight participants’ would use words, while a range like ‘between 100 and 300 participants’ would use numerals.
Style guides also provide instructions on punctuation when writing out numbers. For numbers written as words in body text, it is common not to use commas in the tens and hundreds places for numbers over one thousand. For example, one thousand two hundred thirty-four would be written as “one thousand two hundred thirty-four” rather than “one thousand, two hundred, thirty-four.” Punctuation may also depend on the range – a range written as words like “fifty-five to seventy-eight” would not use commas, but a range written with both words and numerals like “one hundred to three hundred” would typically include commas.
Spelling out precise units of measurement is also prudent, such as in headings, captions or parenthetical expressions. For example, the heading “Results (in Milligrams)” rather than “Results (in mg)”. In financial or mathematical expressions numerals are preferred. And in tables, figures or parenthetical citations, numerals should be used for pagination, issue numbers, chapters and so on.
The choices between writing numbers as words or numerals depend upon factors like context, serial positioning, whether a number is at the beginning of a sentence, and the purpose or emphasis. Being consistent in applying the style guidelines creates a clear, readable flow versus alternating between words and numerals arbitrarily. Understanding and practicing the standards helps achieve academic credibility and professionalism in research writing.