So, you’re deep in the midst of writing your novel. Suddenly, you can’t remember the rule for writing out numbers. Do you spell out 427 or use numerals? Does your character say 24/7 or twenty-four seven? The rules for fiction are not what you learned in college. They do not follow MLA, APA, Chicago Manual of Style, or AP.
The Editor’s Blog published an excellent article addressing the use of numbers and numerals here: http://theeditorsblog.net/2013/01/13/numbers-in-fiction/ Refer to it often. I do!
— Maryjane Stout