"There are three rules for writing a novel," W. Somerset Maugham once wrote. "Unfortunately, nobody knows what they are."
If I had to adapt Maugham's quip to business, scientific and technical writing, I would say, "There is one rule for writing numbers. Fortunately, everyone knows what it is."
Do you?
It's simple: Be consistent.
Here are eight guidelines to help you follow that one simple rule:
1. Spell out numbers less than 10; use figures for numbers 10 and higher (except in scientific and technical writing, where all numbers may be written as figures).
One potato, two potatoes, three potatoes, four — makes 10 potatoes.
2. Spell out numbers that appear as the first word in a sentence (or restructure the sentence to avoid beginning with a number).