Rules For Using Numbers

Rule 1. The numbers one through ten should be spelled out; use figures for numbers greater than ten.

Rule 2. With a group of related numbers where one number is above 10 in a sentence, write the numbers all in figures. Use words if all related numbers are 10 or below.

Rule 3. If the numbers are unrelated, then you may use both figures and words. One through ten should again be spelled out.

Rule 4. Always spell out simple fractions and use hyphens with them.

Rule 5. A mixed fraction can be expressed in figures unless it is the first word of a sentence.

Rule 6. The simplest way to express large numbers is best but be careful to be consistent within a sentence.

Rule 7. Write decimals in figures. Put a zero in front of a decimal unless the decimal itself begins with a zero.

Rule 8. When writing out large numbers of five or more digits before the decimal point, use a comma where the comma would appear in the figure format. Use the word and only where the decimal point appears in the figure format.

Rule 9. The following examples apply when using dates:

The meeting is scheduled for June 30.

The meeting is scheduled for the 30th of June.

We have had tricks played on us on April 1.

The 1st of April puts some people on edge.

Rule 10. Hyphenate all compound numbers from twenty-one through ninety-nine.

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