As a language expert with a focus on academic and formal writing, I've often been asked about the conventions for writing numbers in papers. The rules can indeed be quite varied depending on the style guide one adheres to, but there are some general principles that are widely accepted in English-language writing.

Step 1: Use Words for Small Numbers
The first rule of thumb is to write out numbers from one to nine in words. This is because spelled-out numbers are easier to read and understand at the beginning of a sentence or in a list where they are not accompanied by units or measurements. For example, "Three apples" is more readable than "3 apples."

Step 2: Numerals for Larger Numbers
For numbers larger than nine, the use of numerals is generally preferred. This is especially true when the numbers are accompanied by units of measure or currency, such as "15 miles" or "$20."

**Step 3: Consistency Within a List or Range**
When listing numbers or expressing a range, it's important to maintain consistency. If you start a list with numerals, continue with numerals. The same goes for spelled-out numbers. For instance, if you write "Fifteen," you should not follow it with "twenty-one" but rather "15."

Step 4: Numerals in Scientific Writing
In scientific, technical, and mathematical writing, numerals are almost always used regardless of the size of the number. This is because numerals are more precise and are the standard in these fields.

Step 5: Large Round Numbers
For very large round numbers, it's common to use numerals as well. This is particularly true in financial or statistical contexts where precision is key, such as "1 million" or "3.5 billion."

**Step 6: The Rule of One to Nine and Beyond**
The reference you provided suggests that some style guides recommend using words for numbers up to one hundred or one to ten. However, this can be misleading without context. Generally, for general writing outside of scientific or technical fields, it's more common to use words for one to nine and numerals for ten and above.

Step 7: The Exception to the Rule
There are exceptions to every rule, and writing numbers is no different. For instance, in a historical context, "the year 1000" might be more appropriate than "one thousand" because it adheres to the conventions of historical writing.

Step 8: The Role of Style Guides
Different style guides have different rules. APA, MLA, Chicago, and other guides each have their own recommendations for when to use words or numerals. It's crucial to follow the guide that is most relevant to your field or the publication you are writing for.

Step 9: Context Matters
The context in which a number is used can also dictate whether to use words or numerals. For example, in a narrative, you might use "two" to maintain a conversational tone, but in a data-heavy report, "2" might be more appropriate.

Step 10: Clarity and Readability
Ultimately, the goal is to ensure clarity and readability. If a number is complex or if using words would make it easier for the reader to grasp the magnitude, it might be better to spell it out.

In conclusion, the rules for writing numbers in a paper are not set in stone and can vary widely. However, by adhering to the principles of clarity, consistency, and the conventions of your field or publication, you can make the right choice.

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For general writing, most guides agree that you should use words for the numbers one through nine, but for larger numbers the rules vary wildly from style guide to style guide. Some say to use words for the numbers one to one hundred, one to ten, any word that can be written with one or two words, and so on.Mar 28, 2008read more >>