If you can write out a number in one or two words, do so. Use figures for longer numbers.
If one of several numbers of the same kind in the same sentence requires a figure, you should use figures for all the numbers in that sentence.
When a sentence begins with a number, either spell out the number or rewrite the sentence.
In general, use figures for the following:
ADDRESSES | 23 Main Street; 175 Fifth Avenue |
DATES | September 17, 1951; 6 June 1983; 4 bce; the 1860s |
DECIMALS AND FRACTIONS | 65.34; 8½ |
EXACT AMOUNTS OF MONEY | $7,348; $1.46 trillion; $2.50; thirty-five (or 35) cents |
PERCENTAGES | 77 percent (or 77%) |
SCORES AND STATISTICS | an 8 – 3 Red Sox victory; an average age of 22 |
TIME OF DAY | 6:00 am (or a.m.) |