Writing Numbers
English has many rules for writing numbers and just as many authorities disagreeing with each other about them. Here are some general rules that you may wish to keep handy.
Rule: Spell out single-digit whole numbers.
Example: I would like five copies.
Rule: Use numerals for numbers greater than nine.
Example: I would like 10 copies.
Rule: Be consistent within a category. If you choose numerals because one of the numbers is greater than nine, use numerals for all numbers in that category. If you choose to spell out numbers because one of the numbers is a single digit, spell out all numbers in that category.
Examples:
My 10 cats fought with their 2 cats.
OR
My ten cats fought with their two cats.
Incorrect: I asked for five pencils, not 50.
Rule: If you have numbers in different categories, use numerals for one category and spell out the other.
Example: Given the budget constraints, if all 30 history students attend the four plays, then the 7 math students will be able to attend only two plays.
Note that students are represented with figures and plays are represented with words.
Examples:
I asked for 30 pencils for my five employees.
I have 10 toes but only one nose.
Quiz:
A or B?
1. A. I have 11 cats and two turtles. B. I have eleven cats and 2 turtles.
2. A. We have 23 people in our class. B. We have twenty-three people in our class.
3. A. I need 3 pieces of paper, not twelve. B. I need 3 pieces of paper, not 12.
Answers:
1. A
2. A
3. B


April 15, 2007 at 2:43 am
She gets up at four thirty! Should we not use a dash between four and thirty?
April 16, 2007 at 2:22 am
According to the Chicago Manual of Style, no hyphen is used with time.
April 18, 2007 at 7:53 am
Hello, I would like to know how to write out the numbers 138 and 100.38 if they are not monetary numbers, please?
When I was at school (I am not English native speaker?, I was taught that an “and” should only be added between the hundred and ten (twenty……), eg.
123 one hundred and twenty three
123,456 one hundred and twenty three thousand four hundred and fifty six
123.45 one hundred and twenty three point four five
Am I correct? If not, could you please tell me what is the correct way to write out these numbers?? Thanks!
April 18, 2007 at 2:59 pm
No “and” except to replace a decimal point.
123 = one hundred twenty-three (Do use the hyphen for all compound numbers from twenty-one through ninety-nine.)
23.45 = twenty-three and forty-five hundredths
April 21, 2007 at 10:55 pm
How does one go about age in writing? Should one spell the age or use numerals? Ex.: “A twenty-year-old student” vs. “A 20-year-old student.” Thanks!
April 21, 2007 at 11:12 pm
Both “twenty-year-old student” and “a 20-year-old student” are correct.
May 2, 2007 at 4:33 pm
Thank you Jane; this was most helpful.
May 2, 2007 at 6:59 pm
When writing numbers of different denominations, is consistency the key, e.g., $25 instead of $25.00 and (in the same sentence) $400 (no zeroes).
“I earned $25 for a total of $400 . . . ”
Thank you.
May 2, 2007 at 8:48 pm
Yes.
May 17, 2007 at 4:23 am
Today, I’ve notice the time of day written without the periods after
6pm. Is this correct?
May 17, 2007 at 11:08 pm
You can write PM, p.m., or pm
April 4, 2008 at 1:25 pm
When writing the age of a person or object, what is the correct placement of hyphens? For example, do you write, “the sixteen-year-old boy” or “the seven-year old program”?
April 4, 2008 at 2:48 pm
the sixteen-year-old boy
the seven-year-old program
April 7, 2008 at 1:45 pm
How would I correctly write “project cost of $1 to 3 million…” Is the dollar sign needed in the second instance?
April 7, 2008 at 2:11 pm
I recommend using “cost of $1 to $3 million.”
July 27, 2008 at 6:28 pm
I would like to know if you put dashes in between four and a half, etc.
July 27, 2008 at 11:11 pm
Kris,
Use the hyphen this way: four and one-half
I’m not sure that you would use a hyphen if you write “four and a half.”
November 12, 2008 at 7:25 am
When describing the length of an object, which one is correct?
It is 82-metre long. OR It is 82 metres long.
It is an 82-metre-tunnel.
Thanks^^
November 12, 2008 at 3:55 pm
82 metres long (or meters in American English)
82-metre tunnel
June 30, 2009 at 5:58 pm
What about consistency with age i.e.
“Prince Michael, 12, Paris, 11, and Prince Michael II, seven,”
is this correct?
cheers
June 30, 2009 at 6:02 pm
You would want to be consistent: Prince Michael, 12; Paris, 11; and Prince Michael II, 7.
September 12, 2009 at 4:37 pm
I have a hyphen conundrum.
Which is correct? Or are they both right? And Why?
When I was seven-years-old, my brothers dared me . . .
or
When I was seven years old, my brothers dared me . . .
September 12, 2009 at 7:14 pm
When the age is used as an adjective followed by a noun, hyphenate.
Examples: He is a seven-year-old boy.
He is seven years old.
July 4, 2010 at 4:21 pm
Is this correct in casual and formal writing?
In my 20s and 30s, I rode a bike.
July 5, 2010 at 9:51 pm
Yes, it is correct to write the following: In my 20s and 30s, I rode a bike.
August 13, 2010 at 1:39 pm
What is the difference between
She is a 9 year old girl. and She is 9 years old.
Why is year plural in one and singular in the other and why do we add an article ‘a’ and it changes to singular (year)
August 13, 2010 at 6:43 pm
She is a 9-year-old girl.
Use hyphens to form a compound adjective in front of a noun.
She is 9 years old.
There is no noun following so no hyphens are used.