Numbers

Numerals/numbers

• The most common, Arabic numerals, are 0, 1, 2, etc.
• Roman numerals use the letters I (1), V (5), X (10), L (50), C
  (100), D (500), M (1000) and are used number wars, sequence in family,
  rulers, vehicles, major headings in documents.
• Cardinal numbers are 0, zero, 1, one, etc.
• Ordinal numbers are 1st, first, 2nd, second, etc.
• In general, write out the first nine cardinal (1-9) numbers
  (except for address numbers 2-9, dates, decimals, game scores, highways,
  latitude/longitude, mathematical expressions, measurement/weight,
  money/financial data, percentages, proportion, scientific expressions,
  statistics, technical expressions, temperature, time, unit modifiers,
  votes, and numbers not written out in a proper noun) and any number that
  begins a sentence; use figures for 10 and above.
• The first nine ordinal (1st-9th) numbers are usually written
  out, especially when describing order in time or location.
• Governmental, political, and military units numbered one hundred
  or less are usually written out. Labor unions and other organizations often use figures.
• Numbers of one million and above are easier to read if written
  as figures with the word `million’, `billion’, etc.
• Written-out numbers between 21 and 99 and hyphenated.
• Figures of four digits may be written with or without a comma.
• Numbers of checks, contracts, military hours, pages, policies,
  rooms/suites, streets, telephone numbers, and years are written without
  commas.
• Check, telephone, and serial numbers may contain hyphens.
• A fraction used as a modifier is hyphenated, e.g. three-quarter
  time.
• A fraction used with a whole number is written as a figure,
  e.g. 5 1/2, as are measurements that are fractions, e.g. 1/10 mile.
• A measurement as a modifier is hyphenated, e.g. nine-pound boy.
• Numbers in a series or set are written alike, e.g. `50 to 60
  participants’.
• Street names that are numbers are written out, but may also be
  written as figures from 13 and over.
• Document divisions are usually written as figures, e.g. Psalm
  100, page 7.
• Ordinal numbers are not used in full dates; commas are not used
  in between just a month and year.
• Money designations of one or two words are often written out,
  e.g. one dollar.
• Times are usually spelled out in text and may be when used with
  `o’clock’. Figures are used for exact times, e.g. 8:13. Times may be used with a.m./A.M.,
  p.m./P.M., `o’clock’, or `in the ~’ but those designations should not be
  combined.
• Year and page numbers may omit hundreds and replace with a
  dash, e.g. 1989-90, pp 140-50.
• If an abbreviation or symbol is used with a number, it should
  be written as a figure.
• Numbers should not be divided at the end of lines.
• Plurals of written-out numbers are formed by adding `s’ or
  `es’.
• Plurals of figures are formed by adding `s’ or `’s’.