- Hyphens separate numbers in a series, such as telephone numbers, social security numbers, and bank account numbers. They may also separate section and chapter numbers from page numbers. Example: See pages 3-1 through 3-5.
- Use hyphens with compound modifiers for age. Examples: Mostly 13-year-old girls shop at that store OR the class was for 10-to 12-year-olds. Use the hyphens even if you are spelling out the numbers, as in “four-year-old boy.”
- Use hyphens with ratios and odds when you’re writing numerals. Example: The odds were 5-1 OR the ratio was 1-3.
- For many fractions under one, use a hyphen when you’re spelling out the fraction. Examples: three-quarters of a mile, four-fifths of the pie. Exceptions are fractions that include the word “one,” such as: one half, one third, and one quarter.
Last week, Rose’s Red Pen described when to use hyphens with compound modifiers. Hyphens sometimes accompany numbers as well. When do you add a hyphen with numbers? Here are four general rules:
The rules above will help you remember when to use a hyphen with numbers. If in doubt, check a style guide or see if adding the hyphen helps with clarity of meaning.
Rose Ciccarelli offers writing and editing services through Rosebud Communications.