I want five copies.
I want 15 copies.
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.
Correct I asked for 5 pencils, not 50.
Correct My ten cats fought with their one cat. Their cat won.
Incorrect I asked for five pencils, not 50.
Rule 3. If the numbers are unrelated, then you may use both figures and words. One through ten should again be spelled out.
I asked for 30 pencils for my five employees.
My nine cavities are exceeded in number by my 14 teeth.
My ten toes exceed in number my one nose.
Rule 4. Always spell out simple fractions and use hyphens with them.
One-half of the pies have been eaten.
A two-thirds majority is required for that bill to pass in Congress.
Rule 5. A mixed fraction can be expressed in figures unless it is the first word of a sentence.
We expect a 5 1/2 percent wage increase.
Five and one-half percent was the maximum allowable interest.
Rule 6. The simplest way to express large numbers is best but be careful to be consistent within a sentence.
4 million dollars OR $4 million OR four million dollars (not $4,000,000)
Correct You can earn anywhere from $500 to $5,000,000.
Incorrect You can earn anywhere from $500 to $5 million.
Correct You can earn from five hundred to five million dollars.
Incorrect You can earn from $500 to five million dollars.
Rule 7. Write decimals in figures. Put a zero in front of a decimal unless the decimal itself begins with a zero.
The plant grew 0.79 of a foot in one year.
The plant grew only .07 of a foot this year because of the drought.
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.
$15,768.13 (Fifteen thousand, seven hundred sixty-eight dollars and thirteen cents)
$1054.21 (One thousand fifty-four dollars and twenty-one cents)
Note: The comma is now commonly omitted in four-digit whole numbers.
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.
Forty-three people were injured in the train wreck. Twenty-three of them were hospitalized.
Rule 11. Write out a number if it begins a sentence.
Twenty-nine people won an award for helping their communities.
That 29 people won an award for helping their communities was fantastic!
The Blue Book of Grammar and Punctuation
©1977–2006 by Jane Straus
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