It is generally best to write numbers from zero to one hundred in a non-technical script. In scientific and technical writing, the dominant style is to write numbers. see the publication manual. 32-6. guidelines on the use of numbers versus words. Use the numbers 1, 2, 3, etc. for the following: , In general, words should be used from zero to ten, and numbers beyond. The same rule should be applied to ordinal numbers, i.e. use words for the first, 9. Two numbers side by side. It can be confusing if you write "-ans", so write one of them as a number, like "-ans". Choose the number that contains the fewest letters. 10. Ordinal numbers and consistency. Don't say "He was the first true love", but rather "He was my first true love".