Writing numbers in numerals or words?

There are no official rules for writing numbers, but a general rule of thumb, however, is to spell out small numbers ranging from one to ten and use numerals for larger numbers (i.e. above ten). But there are a few exceptions:

  1. Consistency
    When mixing small and large numbers, you should use numerals.

    The company has 29 employees, of which14 are production workers, 10 are vendors and 5 are administrative staff.
     
  2. Two numbers next to each other
    When writing a sentence that has two numbers side by side, it is best to write one number as a word and the other as a numeral

    He was to translate two 8-page documents by the end of the week.
     
  3. Numbers starting a sentence
    You should never begin a sentence with a numeral. Spell out the number or try to reword the sentence.
     
  4. Many numbers
    When using numbers frequently in a document, it is appropriate that you write all numbers as numerals.