Number Rules : Words Or Digits

[cilineelzein02]

-One of the number rules is that when a number begins a sentence , it must be written as word ( spelled out ).
for example : Twelve participants were involved in the research study.

-Another rule is when a number is followed by a unit , or when it represents an amount, it must be written as a digit.
for example : Each session was of 20 minutes duration.

-And of course 9 and below written as words, 10 and above written as digits. (general rule)

MY QUESTION IS : What if there is a sentence that begins with a number followed by a unit , do I write it as a digit or a word ?
for example : ____ (20) minutes were spent in that project.

[JimF]

These are really examples of usage rather than rules. Just as many organisations will write the numbers from one to twelve with letters and the rest with digits, irrespective of whether they are qualifying a unit or not.

[Arksided]

I was taught (Grammar School) that if you use words in a sentence stating the number then stay with that format, If you're using digits then also stick with that format don't mix them in the same sentence.

[THECORBYLOON]

I tend to write one to ninety-nine as words and anything greater than that as digits.

I would normally write that our nearest town is about, "nine mile away" and not, "9 mile away".

[bobbinwales]

There are conventions am sure but not rules. Whose your audience , that is whose going to read it?

[jno]

Twenty minutes, as per your first rule. Every publisher has its own rules, though, and they're for internal consistency rather than because there's a right way and a wrong way. If you're just texting a friend, write as you please.

[Tuvok]

The format we use in the book that I'm updating is eg.

Two whatever, level 1, year 1, 12 hours

[bhg481]

I would re-phrase the sentence to avoid the problem ie, The time spent on that project was 20 minutes.

[THECORBYLOON]

You could write, "...twenty minute." either is acceptable.

[goodgoalie]

Wait till you have to get your head round adjective order in English - something native speakers do without thinking:

https://www.grammarly.com/blog/adjective-order/

[JimF]

Not to mention phrasal verbs which drive learners crazy!

No sooner had the batsman run out onto the field than his luck had run out and he was run out.

[goodgoalie]

"James while John had had had had had had had had had had had a better effect on the teacher"

[JimF]

Yeah, that's a well-known one. Needs some punctuation :-)

[goodgoalie]

Yes:
James, while John had had "had had", had had "had"; "had had" had had a better effect on the teacher.