Numbers
Learning Objective:  Identify when to use words to refer to numbers and when to use Arabic numerals.

LESSON
Writers usually write out numbers they can write in a word or two and use Arabic numeralsArabic numerals are the ten digits: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9. (0, 1, 2, 3...) to express larger numbers. However, most writers also follow a set of general guidelines about which numbers should be written out and which should be expressed in numerals. In this lesson, you will learn when to use words and when to use numerals to express various numbers.
Words
Numbers should be written out in these situations:
 Numbers expressed in two words or less. Write out and hyphenate any number between twentyone and ninetynine. Numbers outside this range do not require a hyphen.
Eleven students
One hundred books
Seventynine animals
Thirtyfour days
Fiftyfive miles per hour
 Large rounded numbersNumbers that have been increased or decreased to the nearest whole number. Examples: 1,050,129.88 is rounded down to 1,050,000.00.Numbers that have been increased or decreased to the nearest whole number. Examples: 1,050,129.88 is rounded down to 1,050,000.00 or estimated numbersNumbers that are not exact, but instead formed from an educated guess, usually a rounded number. Examples: about fifty million..
Five trillion
Five thousand
Seven hundred
 Numbers at the beginning of a sentenceA group of words, phrases, or clauses that expresses a complete thought. A complete sentence has these characteristics: a capitalized first word, a subject and a predicate, and end punctuation, such as a period (.), question mark (?), or exclamation mark (!).. If the number is so large that it would be awkward to write out, rephrase the sentence so that the number is not the first word.
Four hundred and two staff members are in that unit. This could be rephrased to avoid the number at the beginning of the sentence: There are 402 staff members in that unit.
Twentyfive trucks arrived with supplies.
 Numbers in dialogueSpoken conversation described in written form, such as the script for a movie..
"Sabrina swam five hundred and seven laps," he marveled.
"I put two hundred and twenty pieces of candy in the jar," she announced.
"How long will it take you to run a hundred and thirtyfive miles?" he asked.
 CenturiesA period of one hundred years. Example: the twentieth century includes the years from 1901 to 2000. and decadesA period of ten years. Example: the decade of the nineteennineties includes the years from 1990 to 1999.. These should be lowercase.
The nineteenth century
The eighties
The roaring twenties
 OrdinalA number that shows order. Examples: first, third, fifteenth. numbers, such as first, second, and third
Her first birthday
My second cupcake
His fifth time around the track
 Simple fractions
One fourth of an ounce
One half of a cake
Two thirds of the pie
 Time of day with "o'clock" and on the half and quarter hour.
Five o'clock
Half past two
A quarter past ten
Numerals
Arabic numerals are the ten digits: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9. The following types of numbers are usually expressed as Arabic numerals:
 DecimalsA number that is written with a dot between the whole number and the part of the number that is less than one. Examples: 3.75 grade point average; 8.5 ounces.
7.5 ounces
2.5 grams
3.13 pounds
 Specific time of day. Use noon or midnight instead of 12.
3:35 p.m.
4:47 a.m.
12:25 p.m.
 Dates and years
July 22, 1954
April 3, 1966
September 9, 2011
 Scores
The final score was 28 to 14.
She won the game 8 – 6.
He never recovered from the 15 – 14 loss.
 Money references
He owed her $216.30.
She gave him $14.65.
Her change was $4.23.
 Mixed numbers
Mix in 3 ½ cups of flour.
Her waist was 25 ¼ inches around.
Give him 2 ¼ tablespoons of the medicine after every meal.
Other Rules
There are a couple of other rules to keep in mind when you use numbers in your writing:
 Be consistent.
It is important to treat related numbers in a sentence consistently. If you choose to use Arabic numerals, then use them throughout that sentence. The same is true if you choose to write out numbers. You can bend the guidelines for using numbers if you have a purpose and are consistent.
Incorrect: Each of the 12 children sorted out seventyfive cans of food for donation.
Correct: Each of the twelve children sorted out seventyfive cans of food for donation.
Also correct: Each of the 12 children sorted out 75 cans of food for donation.
 When in doubt, check your style guideA set of rules for punctuation, grammar, and other facets of writing, used to produce consistency and promote understanding. Different publications and types of writing often follow different style guides. Wellknown style guides in the U.S. include The Chicago Manual of Style, the MLA Style Manual, and the Associated Press Stylebook.. While the general rules above will suit most situations, there is some variation between MLAA grammar and reference guide used mainly by students and scholars writing about the humanities (languages and literature). , APAA set of guidelines for citing sources used in literary and academic writing. APA style is most commonly used in the social sciences., APA punctuation and grammar guide used mainly in journalism, public relations, and advertising., and The Chicago Manual of StyleA set of guidelines for grammar, punctuation, and citations, widely used by students, editors, and general interest publications..
+ PRACTICAL APPLICATIONMany types of writing that you will do in college and in your career will require that you know how to write with numbers. For example, most of the writing that you will do for courses in science, math, technology, and other fields will require you to develop this skill. In addition, you will need to know how to write with numbers in order to quantify your skills in cover lettersA letter that is sent along with a resume that provides context and more information for the reader. and resumesA brief written history of a person's education, work, and volunteer experience, submitted for the purpose of obtaining a job., and many jobs will require that you do technical writing that involves numbers. Knowing how to apply the rules in this lesson will ensure that your writing is appropriate and easily understood.
+ EXAMPLEEach of the following sentences uses numbers in some way. Notice whether the situation requires words or numerals and why.
 "We'll need (125, one hundred and twentyfive) balloons for the parade," the mayor said.
Answer: one hundred and twentyfive
The number is written out in dialogue.
 Disco was popular in the (70s, seventies).
Answer: seventies
The number names a decade, so it should be written out.
 We left for the party at (7:00, seven o'clock).
Answer: seven o'clock.
The number tells the time of day with "o'clock," so it should be written out.
 Her alarm went off at (6:36, six thirtysix) a.m.
Answer: 6:36.
The number tells a specific time, so numerals are used.
 It's my (1^{st}, first) time snowboarding.
Answer: first
The number is an ordinal number, so it should be written out.
 The ship finally arrived on (August 24, 1821; August twentyfourth, eighteen twentyone).
Answer: August 24, 1821
Numerals are used in a date.
 Since (1/3, one third) of the students are out of school, I can't give the test.
Answer: one third
The number is a simple fraction, so it should be written out.
 (250, Two hundred and fifty) workers went on strike.
Answer: Two hundred and fifty.
The number begins a sentence, so it should be written out.
 The Browns beat the Patriots (21 – 14, twentyone to fourteen).
Answer: 21 – 14
The numbers are part of a score, so numerals are used.
 I made (35, thirtyfive) cupcakes, one for each child.
Answer: thirtyfive
The number is expressed in two words, so it should be written out and hyphenated, since it is between twentyone and ninetynine.
+ YOUR TURNEach of the following sentences uses numbers in some way. Read the sentences and choose whether the situation requires words or numerals and explain why.
 "The final tally is (404, four hundred and four)!" shouted the announcer.
four hundred and four
The number is written out in dialogue.
 He studies religious movements of the (18^{th}, eighteenth) century.
eighteenth
The number names a century, so it should be written out.
 She's usually home by half past (5, five).
five
The number tells the time of day with "half past," so it is written out.
 She weighed only (5.5, five point five) ounces at birth.
5.5
The number is a decimal, so numerals are used.
 The (3^{rd}, third) dress is my favorite.
third
The number is an ordinal number, so it is written out.
 I'll meet you at the theater at (7:45, seven fortyfive).
7:45
The number tells a specific time, so numerals are used.
 While all the members had planned to come, only (1/2, one half) showed up.
one half
The number is a simple fraction, so it is written out.
 (450, Four hundred and fifty) textbooks will be ordered for the coming year.
Four hundred and fifty
The number begins a sentence, so it is written out.
 The bill for dinner came to ($216, two hundred and sixteen dollars).
$216
The number is an amount of money, so numerals are used.
 I counted (7, seven) chickens in the yard.
seven
The number is expressed in less than two words, so it is written out.
+ METACOGNITIVE QUESTIONWhy is it important to know whether to use words or numerals when writing?
I will need to use numbers when I write in college and in my career. If I use numbers correctly, my writing will be more easily understood. Using numbers correctly shows attention to detail and reflects well upon the rest of my writing.
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