Grammar Fractions, Decimals, and Money |
The Blue Book of Grammar and Punctuation

Fractions, Decimals, and Money

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

Example: One-half of the pies have been eaten.

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

Example: We expect a 5 1/2 percent wage increase.
Example: Five and one-half percent was the maximum allowable interest.

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

Example: Forty-three people were injured in the train wreck.

Rule: Replace a decimal point with and when you write out amounts on a check. You may use numerals in fraction form for cents.

Example: Fifty-two and 46/100 (“Dollars” will already be printed at the end of the line.)

Rule: Express large numbers simply. Be careful to be consistent within a sentence.

Correct: You can earn from one million to five million dollars.
Incorrect: You can earn from one million to $5,000,000.
Correct: You can earn from $500 to $5,000,000.
Correct: You can earn from five hundred dollars to five million dollars.
Incorrect: You can earn from $500 to five million dollars.

Rule: Write decimals in figures. Place a zero in front of a decimal as a courtesy to the reader.

Example: The plant grew 0.79 of a foot in one year.
Example: The plant grew only 0.07 of a foot this year because of the drought.


Pop Quiz: Correct or incorrect?

1. Eighty one people were injured in the train accident.
2. I wrote a check for $300, not $3,000.00.
3. Hair grows one fourth of an inch per month.
4. The tree grew .95 of a foot because of a wet winter.


Pop Quiz Answers: All sentences were incorrect.

1. Eighty-one
2. $3,000 (no .00)
3. one-fourth
4. 0.95

If the article or the existing discussions do not address a thought or question you have on the subject, please use the "Comment" box at the bottom of this page.

86 responses to “Fractions, Decimals, and Money”

  1. Brandi Bergheimer says:

    I was wondering if it was supposed to be five and a half or five and a half? I remember that there was some funky rule about ‘A’ verses “AN” in this type of setting. Please help. Thank you Brandi

    • Jane says:

      I think you mistyped but the correct way to write this is as follows: five and a half.

      • irvan says:

        If i write down five a half is that same with 5 1/2?thanks before

      • Laura says:

        How do you correctly refer to different currencies, especially when writing to an international (but English-literate) audience? Many countries use the dollar sign, for example, but it isn’t necessarily the US dollar that is being referenced. Which, if any, of the following is (are) correct?
        USD 100
        USD $100
        $100 USD

        Thanks for your help!

        • Since the abbreviation USD stands for “US dollars,” and the dollar sign means “dollars,” using them together is redundant. We are not aware of any generally accepted standardization in this area, but from what we’ve seen, we recommend writing USD100, USD 100, US$100, or US$ 100, staying consistent within your document.

  2. Tristan says:

    I was wondering if there are any rules regarding where the dollar sign should go when using parenthesis to display a negative number. Is it $(500) or ($500)? The “Accounting” format in excel would display it as: $(500). Is that correct? Are both acceptable?

    • The use of parentheses to indicate a negative number is typically seen on spreadsheets, not in formal writing, to which our rules apply. Rule 1 in the Parentheses section of says, “Use parentheses to enclose words or figures that clarify or are used as an aside.” Thus, in formal writing, parentheses would not indicate a negative number.

      Example: I expect five hundred dollars ($500).

      In most formal writing, use the minus sign to indicate a negative number.
      Example: -$500

      • Michael says:

        In reference to negative numbers in paragraphs, where is the source of your information that provides the support that negative numbers should not be in parenthesis for formal writing?

        • We are unable to find any authoritative source that recommends the use of parentheses with negative numbers in formal writing. As shown in Rule 1 of Parentheses and Brackets on our website, parentheses are normally used in sentences to enclose information that is clarifying or used as an aside. Our example is: He gave me a nice bonus ($500). It would be confusing to use parentheses to indicate negative numbers in formal writing. However, parentheses are commonly seen to indicate negative numbers in tabular formats such as spreadsheets.

  3. Bill says:

    Isn’t it “one-million to five-million dollars?” Aren’t one- and five-million compound adjectival modifiers?

    • As described in our blog post “Numbers as Adjectives,” you would hyphenate when a number and a measurement unit taken together form an adjective, that is, when they describe another object. An example would be “a five-million-dollar deficit.”

      • Bill says:

        Doesn’t my previous point stand? To use your example — five-million-dollar deficit — isn’t it equally appropriate to hyphenate, e.g., five-dollar deficit? Therefore, my original example, ” one-million to five-million dollars,” (originally yours without hyphens) stands, and, in fact, would be better expressed thusly: “one- to five-million dollars.” ??

        Thanks. Lots of fun.

        • Grammatically speaking, there is no difference between five million dollars, 12 hours, 25 yards, four pounds, etc. They are simply numbers with their unit definitions. The important phrases from the “Numbers As Adjectives” blog that I used below is, “hyphenate when a number and a measurement unit taken together form an adjective, that is, when they describe another object.”

          Notice the difference between:
          five million dollars vs. five-million-dollar deficit (or five-dollar deficit, quantity doesn’t matter)
          12 hours vs. a 12-hour shift
          25 yards vs. a 25-yard lead
          four pounds vs. a four-pound hammer

          Similarly, in expressing a range:
          Next year, we expect our deficit to range from one to five million dollars. vs. Next year, we expect a one- to five-million-dollar deficit.

  4. Stefanie says:

    In the Grammar books I use, the rule for fractions states that when the fraction is being used as an adjective, you hyphenate it. (Ex. Two-thirds majority won the vote.)
    When you use the fraction as a noun, you don’t use the hyphen. (Ex. Two thirds of the pie was eaten. Two thirds here is the subject and therefore gets no hyphen.)

    • The style manuals that we consulted do not agree with you. The Chicago Manual of Style’s rule (9.14) says, “Simple fractions are spelled out. For the sake of readability and to lend an appearance of consistency, they are hyphenated in noun, adjective, and adverb forms. In the rare event that individual parts of a quantity are emphasized, however, as in the last example, the fraction is spelled open.”

      She has read three-fourths of the book.
      Four-fifths of the students are boycotting the class.
      I do not want all of your material; two-thirds is quite enough.
      A two-thirds majority is required.
      We divided the cake into four quarters; I took three quarters, and my brother one.

      Also, The Associated Press Stylebook says, “Spell out amounts less than 1 . . ., using hyphens between the words: two-thirds, four-fifths, seven-sixteenths, etc.”

  5. Ha Nguyen says:

    I am studying a fraction and I ask you how to use a fraction
    For example,
    1) 3/4 of an egg is ripe. Is it right ?
    (I am wondering 3/4 of + N, N may be countable or uncountable) and N must be definite ?
    2) How to use percent is the same way as such 3/4

    Thank you in advance.

    • A fraction or percentage is normally used with a countable noun. An egg cannot be ripe nor can it be easily divided into three quarters (unless it’s hard boiled). I have never seen a recipe that calls for a fraction of an egg. You could say 3/4 cup of egg whites, 3/4 of the eggs are brown, or 75% of the eggs are brown.

  6. Lynn Weston says:

    Is it correct to use fractions with metric units and vice versa? Ex: 205.5 pounds or 1/2 cm Thanks.

    • It is correct to use decimals with metric units, but not fractions. Fractions are acceptable in the United States customary unit system, however, if you are including conversions you should be consistent and use only decimals. Examples:
      .5 cm
      72.5 kg
      2 1/2 lbs. OR 2.5 lbs.
      5 1/2 ft. OR 5.5 ft.

  7. Paula Barnett says:

    How would I write “A $30 dollar donation is requested.” Is that correct or should I write out thirty? Also, is there a hyphen between $30 and dollar since it’s modifying donation?

    • The dollar sign ($) indicates “dollar.” We do recommend a hyphen in the spelled-out version, since it is a compound adjective.
      A $30 donation is requested. OR
      A thirty-dollar donation is requested.

  8. cindy says:

    How would I write $4,200,000? Do I round down? Any assistance would be greatly appreciated.

    • The simplest way to express large numbers is usually best. We recommend writing the number as you have written it. Or you could use Associated Press style, which would write it “$4.2 million.”

  9. Alex says:

    Is a hyphen required when writing out $4 dollars.
    Ex. Four-dollars.
    Ex. Four-dollars and 50 cents
    Thirty-four dollars and 50 cents

    • Since four dollars is not a compound adjective, do not hyphenate. The number thirty-four is hyphenated. We recommend that you be consistent with using numerals or spelling out numbers:
      Four dollars and fifty cents OR $4.50
      Thirty-four dollars and fifty cents OR $34.50

  10. Dru says:

    Is there a rule for awkwardly cumbersome fractions? Specifically, if something is measured as 837 feet 8 13/64 inches long, how is that written? I’ve seen the following variations. Are any of them correct?

    “…measured 837 feet 8 13/64 inches long…”
    “…measured 837 feet 8 and 13/64 inches long…”
    “…measured 837 feet 8-13/64 inches…”


    • Although the style books do not specifically refer to whole numbers with fractions as complex as the one in your sentence, we recommend writing “…measured 837 feet 8 13/64 inches long…”.

  11. Kristin says:

    Are inches and feet referred to correctly in the following sentences?

    The art will be created with 160 three inch anodized aluminum pipes that a one-quarter inch wall. The sculpture will be approximately 15′ x 50′ x 12′. The pipes will be submerged 5′ into the ground and are aluminum so there will be minimal maintenance.

    Also what is the rule about spelling dollar amounts in a formal document? For instance, is the following correct?

    Public art in a form to be approved by the Legal Department with David Parker, in the amount of Eighty Four Thousand Dollars ($84,000.00).

    Does the dollar amount have to spelled out every time the amount is referred to in the document for consistency?

    • Because parts of your sentences are difficult to comprehend, we will address only your direct questions regarding inches, feet, and writing dollar amounts. We recommend staying consistent in your sentences. If you choose to write “inches” in your first sentence, write “feet” in your second sentence. The compound adjectives three-inch and one-quarter-inch require hyphens.

      The Chicago Manual of Style’s Rule 9.25 says, “Sums of money of more than one hundred dollars are normally expressed by numerals.” Therefore, we feel that expressing the amount of money as “$84,000” is adequate unless your legal department requires that it also be spelled out. In that case, the spelled-out portion should be written as “eighty-four thousand dollars.”

  12. Claire says:

    Is it ever possible to use the following decimal point:
    “The cost of the class is $79. for the entire semester.”

  13. Mary says:

    What is the proper way to annotate foreign currency such as the GBP? for example fifteen hundred dollars is $1500.00 or $1,500.00 but are commas and decimal used for pounds? ie: fifteen hundred pounds = £1500.00 or £1,500.00


    • In the English-speaking world, it is common to use commas every three decimal places in numbers of four or more digits, counting right to left. Decimals are not necessary unless there is a fraction.

  14. Lori says:

    If I’m writing a price range, do I use the dollar sign on the second number?

    $1,000-3,000 or $1,000-$3,000

    Thank you!

  15. Oscar says:

    I have a question. Do I use another dollar sign between hyphens? Like this “$50-$100” or just “$50-100”? I would really like claification as in whether or not I use another dollar sign when there’s a hyphen.

    • As we responded to Lori on July 2, 2015, The Chicago Manual of Style’s Rule 3.81 recommends repeating the dollar sign when writing number ranges that include dollar amounts.

  16. Kathy says:

    Our copy editors are in disagreement about how to render hyphens in spelled our fractions in the context of a elementary-school math book in which we are instructing children how to write out numbers (it’s a Common Core skill–no getting around it). If we follow Chicago, as we usually do, and use a hyphen between the numerator and denominator, what do we do with complex fractions such as 37/300? And how would we differentiate between 2/100,000 and 200/1000?

    • Your example shows why we do not recommend spelling out complex fractions. The following are our best guesses:
      thirty-seven three hundredths (37/300)
      two hundred-thousandths or two one hundred-thousandths or one fifty-thousandth (2/100,000)
      two hundred thousandths or two hundred one-thousandths or one-fifth (200/1000)

  17. sofia skaf says:

    So what would 16 and 2/4

    • A mixed fraction can be expressed in figures (16½) unless it is the first word of a sentence. We cannot make any other recommendations without seeing the fraction used in a complete sentence.

  18. K Peterson says:

    What is the correct way to state that something costs .00006 of a cent? Is there a dollar sign?

    • While we don’t know what might carry such a cost, writing an obscure number such as this as a monetary amount with a dollar sign could be even further confusing for the reader. We recommend sticking with “0.00006 of a cent.”

  19. Vasilina P. says:

    There is a document where it is needed to state a sum of money both in figures and in letters. The sum is 0.0016 dollars. How I supposed to spell it? sixteen tenthousandth dollar / sixteen tenthousandth of a dollar?

    Thank you in advance

  20. Amanda Lee says:

    What is the rule for a compound adjective that contains a dollar symbol? Is it a $20 million home, or $20-million home? Thanks!

  21. Juliet says:

    I think it is OK to write $3:00 for money but apparently it has to be a period, and the semi colon is only used for time. Is this correct?

  22. Joe says:

    Thanks for a very informative page and good questions and answers.

    Assuming you want to use the dollar sign symbol ($) and you have a negative currency number, which is most common / most preferred:

  23. I am proof reading a grant with various amounts of proposed expenses. One set of figures lists boxes for $174 to $225, later on flowers are referenced from $4.00 to $5.00. Is there a preference for adding the .00 or is up to the writer to be consistent with the use of .00. Or, if there are no cents in any of the figures in the grant, should the .00 be dropped on all figures?

    • The Chicago Manual of Style says, “Whole amounts expressed numerically should include zeros and a decimal point only when they appear in the same context with fractional amounts.”
      Example: Prices ranged from $0.95 up to $10.00.
      If there are no cents in any of the figures in the grant, we recommend using no zeros or decimal points.

  24. Herman says:

    Foot or feet: Questions about length measurements of less than one foot, example: “0.23 foot”. Or is it: “0.23 feet”? If you say it, “Zero point twenty-three feet” sounds better than the same, ending in foot. But then, how about “0.01” – foot or feet? And if it is between one and two feet, is it 1.23 feet or 1.23 foot? More than two feet, I guess it’s always “feet”: 2.23 feet.

    • It doesn’t matter whether the length is more or less than one foot. It depends on how the length is used in the sentence. You would say “the wood is X feet in length.” However, if the decimal is being used as part of a compound adjective, you would say an “X-foot piece of wood.”

  25. Emily says:

    When you refer to “1/8” should it be “an 1/8”, “a 1/8”, or should there be no indefinite article? Or because it is a simple fraction should it be spelled out?

    • It depends on the context. Simple fractions should be spelled out and hyphenated. An article is not always necessary.
      One-eighth cup of water was added to the recipe.
      A one-eighth-inch slit was cut in the fabric.
      The cut in the fabric measured an eighth of an inch.

  26. Roshawn Dobbins says:

    My co-worker said the following phrase is incorrect. All my life I always saw the “$” symbol before numbers and now someone is telling me it is incorrect. See phrase below:
    “For just $20 bucks you can purchase brand new gym clothes and your gym lock.” Should I remove the dollar symbol?

    • The dollar sign ($) indicates “dollars.” The dollar sign and the word bucks should not be used together.
      “For just $20 you can purchase brand new gym clothes and your gym lock.” OR
      “For just 20 dollars you can purchase brand new gym clothes and your gym lock.” OR
      “For just 20 bucks you can purchase brand new gym clothes and your gym lock.”

  27. Echo says:

    How do you express mixed money? Which of the following is correct?
    $10 and 25 cents
    10 dollars and 25 cents

  28. Diane says:

    How do you express fractions at the beginning of a sentence? Example: 15/20 people like ice cream.

    Should the fraction be spelled out or is it acceptable to express it as above?

    • Our Rule 1 of Writing Numbers says, “Spell out all numbers beginning a sentence.” Therefore, write “Fifteen of every twenty people like ice cream,” or “Three of every four people like ice cream.”

      • Joshua Fuerte says:

        How can I spell out numbers with decimal point at the beginning of sentence?

        • We cannot think of a situation where the sentence would not be improved by rewording it so the decimal does not start the sentence. Can you? Or you could spell out the decimal as a fraction, such as “Three-fourths of the tests …”

  29. C. Wade says:

    If the number is a whole number (no cents), is it better to use a decimal (i.e $100.00) or not (i.e. $100)?

    • The Chicago Manual of Style’s Rule 9.21 says, “Whole amounts expressed numerically should include zeros and a decimal point only when they appear in the same context with fractional amounts [other amounts that include cents, such as $98.21].”

  30. Karen says:

    What is correct $15-18.50/hr or $15.00-18.50/hr or $15/hr-$18.50/hr?

    • The Chicago Manual of Style recommends repeating the dollar sign when writing number ranges that include dollar amounts. For consistency, we recommend writing “$15.00/hr.-$18.50/hr.” or “$15.00 per hr.-$18.50 per hr.” You probably could write “$15.00-$18.50/hr.” as most people would understand that “/hr.” is included.

  31. Anar says:

    There is a hundred dollars or There are a hundred dollars?
    50 dollars is enough for me or 50 dollars are enough for me?

    • says:

      Our Rule 7 of Subject-Verb Agreement says “Use a singular verb with distances, periods of time, sums of money, etc., when considered as a unit.” In addition, our Rule 1 of Writing Numbers says, “Spell out all numbers beginning a sentence.” Therefore, write the following:
      There is a hundred dollars. OR There is $100.
      Fifty dollars is enough for me.

  32. Justin Martineau Deschenes says:

    I was wondering can you write 500 dollars?

    • The Chicago Manual of Style recommends numerals with the dollar symbol or the number written out with the word dollars: $500 or five hundred dollars. We consider 500 dollars to be a more informal expression.

  33. brenda says:

    May i ask if it is ok to write .0001 instead of 0.0001? Because the value is still the same, right?

  34. eve says:

    How do I write in words 18.50? Is it eighteen and five tenths or eighteen and fifty hundredths?

    • says:

      As the post states, “Write decimals in figures.” Grammatically speaking, that is our recommendation. Mathematically speaking, the values are the same.

  35. Jill Omen says:

    When expressing dollars and cents, would you ever use superscript for the cents? Would it be underlined? Would there be a decimal between the dollars and cents if indeed you superscript it?

    • says:

      We see no reason to use a superscript to express a monetary amount in cents.

  36. joyce walker says:

    Here’s a sample sentence from something I’m editing: “It costs them less; their cost of labor is $5 an hour, a developed nation, $10 an hour.”
    Would you express the $5 and $10 or five dollars and ten dollars?
    This is in a political economics book.

  37. John DeJordy says:

    Is the following sentence correct if I don’t want to use any numerical numbers?

    “Based on past results, I predict a zero point zero zero one five two percent chance.”

    • says:

      Yes; however, we recommend writing percentages in numerals except when they occur at the beginning of a sentence.

  38. Stephanos says:

    When comparing two percentages, when do we use singular, as opposed to plural? For example:
    “Poling shows that 3.7 percent of the population approve. This is down 0.2 percentage point(s) from last year, when 3.9 percent approved.”
    “Poling shows that 5.7 percent of the population approve. This is down 2.0 percentage point(s) from last year, when 7.7 percent approved.”

    • says:

      Percentage under 1.0 would be singular.
      Polling shows that 3.7 percent of the population approve. This is down 0.2 percentage point from last year, when 3.9 percent approved.
      Polling shows that 5.7 percent of the population approve. This is down 2.0 percentage points from last year, when 7.7 percent approved.

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