• 3-minute read
  • 28th November 2015

How to Use Numbers in Writing

Writing numbers? ‘But that’s easy’, we hear you cry! However, not every student knows the rules that govern the use of numbers in academic documents. Unfortunately, not many people agree on these rules either!

Today, we’re going to look at some widely agreed upon approaches to using numbers in writing. We’ll be using illustrative excerpts from our fictional essay, ‘Aliens Among Us: A Study of Extra-terrestrials in Australia.

Using Numbers in Text

Any numbers below ten are generally written as text in academic documents. As such, in a sentence like this:

We used 7 groups in our study to test for aliens in the human population.

You should replace the number ‘7’ with the word ‘seven’:

We used seven groups in our study to test for aliens in the human population.

However, for numbers higher than ten, you should use numerals:

All in all, we found 7,182 aliens who had been posing as humans.

It’s also important to be consistent when more than one number appears in a sentence, even if this means bending the rules above so that you use the same format for both (usually numerals). For example:

Respondents were aged between seven and 82. – Inconsistent

Respondents were aged between 7 and 82. – Consistent

Remember to check your style guide on this, though, as some approaches recommend writing out numbers up to 100!

Statistics and Measurements

Statistics are usually represented with numerical figures, especially in scientific or technical writing:

We found that 7% of our study sample were not human.

This also applies to measurements:

We found that the blood sample of each alien subject contained, on average, 0.98 mg of Jupiter juice.

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However, in formal, non-technical writing, these numbers and the accompanying measurements/symbols should be written out in full:

We spent ninety percent of the holiday on the beach.

Telephone Numbers

Telephone numbers should, of course, always be in numerals:

Report compiled by I. Amalien, head of Alien research at Melbourne University, telephone no. 05748 511784

Dates and Times

Dates should also be written numerically for the most part:

We first noticed that a significant proportion of the population of Australia could be of extra-terrestrial origin on 14 March 1985.

When talking about whole decades, you can write these out in words or numerals. If you choose numerals, however, remember to never put an apostrophe between the zero and the ‘s’:

The eighties were a tough time to get funding for alien research.

However, in the ’90s, we managed to secure a grant.

The most important thing here is consistency. Choose either use numerals or words and then stick to this throughout your document.

Times of day should be represented in numbers when ‘am’ or ‘pm’ are used:

We took the blood samples at 7am each morning.

However, if you use ‘o clock’, you should write the number in word form:

We administered the truth juice at nine o’clock each evening.

Comments (2)
Belinda
1st June 2022 at 09:06
I'm struggling with editing a document that has lots of different numbering and I wondered if there are any rules about it. E.g. 1. The document starts like this. (1) Then it has this (2) And this followed by 1) this 2) and this 2. Then we finally get to 2. (1) Of course we have this (2) and this again 1) then this and then the weird one Proposal ① Proposal ② I feel like I want to change that last one, but I feel like all the numbers are used up. Proposal A?? Proposal i) and ii) I would be interested if anyone can tell me the rules here. Thanks in advance. P.S. It was a lot easier to understand before my spaces and new lines were deleted. Hope it is still readable.
    Proofed
    1st June 2022 at 09:33
    Hi, Belinda. Apologies about the lack of formatting in comments; this has been reported, so hopefully we can fix it before too long. On the question of the numbering in your document, if I understand you correctly, you're asking how to handle different levels of numbering (e.g. if the '1.' part is a main heading, '(1)' would be a first-level subheading, and '1)' would be the second level of subheading). In terms of the 'rules' here, there aren't any (assuming you're not following a specific style guide; if you are, then check it for advice on heading levels). If you are dealing with heading levels, though, I would recommend applying a consistent style of numbering throughout and using 'decimals' to indicate sublevels (e.g. if the main heading is '1.', the subheadings in that section would be '1.1.', ‘1.2.’, ‘1.3.’ and so on; subheadings within the first subsection would be '1.1.1', ’1.1.2.’, etc.; and the next level down would be '1.1.1.1.', ‘1.1.1.2.’ and so on). This will ensure it is clear which level of heading is which and prevent the untidy mixture of different numbering styles.


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