Grammar School: Numbers

During our July Critique Session, the question of how to write numbers was discussed. This is one of those grammar topics that can, at least on the surface, seem a bit confusing, like the serial comma. But when you drill down and do the research, you can weed through the confusion and master number writing.

The general rule is when a number can be written in two words or less, spell it out. If greater than two words, write the number:

I have ninety-nine erasers in my antique-erasers collection.
My great-grandmother is one hundred years old.
There are seventeen children coming to Lucy's birthday party.
It should take me about six hours to read this 175-page book.

However if you have a series of numbers, aim for simplicity and consistency (spelling out all but 145 would be awkward, so keep it simple):

My lucky numbers are 12, 54, 97, and 145.

Rule exception - any number occuring at the beginning of a sentence is spelled out:

Seven hundred and thirty students attend my son's school.

It gets a little tricky with round numbers, but if you just remember all round numbers are spelled out, you should have it. Here is an excerpt from Grammar & Style at Your Fingertips by Lara M. Robbins:

If the number is larger than 101 but is a round number, then it would also be spelled out. A round number is a number ending with one or more zeros.

• There were an estimated seven hundred fifty million people watching as Diana married Prince Charles.
• There are already more than two thousand bookies taking bets on who will win the next Kentucky Derby.

RANDOM HOUSE WEBSTER'S grammar, usage, and punctuation says that generally (the word "generally" lets you know there are some exceptions), most of the following are written in figure form: dates, decades, pages, dimensions, decimals, percentages, measures, statistical data, exact amounts of money ("When providing references to money in written dialogue or round numbers, spell out the dollar amount" - Lara M. Robbins), designations of time when followed by A.M. or P.M., and addresses. Here are the examples the book gives:

June 24, 1945
the 1920's
124 B.C.
p. 263
p. xxvi
2' X 4'
2.5 cm
0.9631
23 percent
93 miles
$367.27
86%
8:30
4262 B Street

There are exceptions to these I just listed, so be sure to get a good grammar book with a thorough section on number writing. My favorite is Grammar and Style at Your Fingertips by Lara M. Robbins (link above). I do have this book as well at the Random House book I referenced above at all of our Critique Sessions.

Memorize the rules, and familiarize yourself with the exceptions to the rules, and you will have a solid grasp on number writing.

Keep in mind that technical, academic, and business writing as well as many magazines and newspapers follow a common rule of spelling out numbers from one through ten and using numerals for all others. If you purchase a grammar book, make sure it is not a grammar book geared toward business writing (The Gregg Reference Manual is one example) unless your writing falls into one of the categories I just listed. Currently, I am not aware of anyone in our writers' group who writes in any of these categories.

Post by: LWC Director Karen Aldridge. Visit her personal blog at My Writing Loft.