- Although usage varies, most people spell out numbers that can be expressed in one or two words and use figures for other numbers:
- over two pounds
- six million dollars
- after thirty-one years
- eighty-three people
- after 126 days
- only $31.50
- 6,381 bushels
- 4.78 litres
Days and Years
- December 12, 1965 or 12 December 1965
- A.D. 1066
- in 1900
- in 1971-72 or in 1971-1972
- the eighties, the twentieth century
- the 1980’s or the 1980s
Time of Day
- 8:00 A.M. (or) a.m. (or) eight o’clock in the morning
- 4:30 P.M. (or) p.m. (or) half-past four in the afternoon
- 16 Tenth Street
- 350 West 114 Street
- Room 8
- Channel 18
- Interstate 65
- Henry VIII
Page and Division of Books and Plays
- page 30
- chapter 6
- in act 3, scene 2 (or) in Act III, Scene ii
Decimals and Percentages
- a 2.7 average
- 13 1/4 per cent
- .037 metric ton
Large Round Numbers
- four billion dollars (or) $4 billion
- 16,500,000 (or) 16.5 million
Notes on Usage
Repeat numbers in legal or commercial writing.
- The bill will not exceed one hundred (100) dollars.
Numbers in series and statistics should be consistent.
- two apples, six oranges, and three bananas
- NOT: two apples, 6 oranges, and 3 bananas
- 115 feet by 90 feet (or) 115′ x 90′
- scores of 25-6 (or) scores of 25 to 6
- The vote was 9 in favour and 5 opposed
Write out numbers beginning sentences.
- Six per cent of the group failed.
- NOT: 6% of the group failed.
Use a combination of figures and words for numbers when such a combination will keep your writing clear.
- Unclear: The club celebrated the birthdays of 6 90-year-olds who were born in the city. (may cause the reader to read ‘690’ as one number.)
- Clearer: The club celebrated the birthdays of six 90-year-olds who were born in the city.
Numbers that represent time, dates, ages, sizes, scores, money, and points on a scale
- in about 6 years
- 2 days ago
- at 12 noon
- 6-year-old children
Numbers that represent a place in a series
- year 7 of an 8-year project
- room 9
- Figure 2 (in an article)
- Chapter 5
- row 1
Numbers in a list of four or more numbers
- 1, 2, 4, and 8 bits, respectively
Numbers less than 10 that do not represent exact measurements.
- only three times
- four 32-bit words
- eight lists
- nine pages
- a three-way interaction
Any number that begins a sentence, title, or heading.
- Sixteen-bit processors were used.
- Thirteen of 20 processors failed.
- one-fifth of the users
- execution time was reduced by two thirds
- in one half the time
Widely accepted phrases
- the Fourth of July
- the Ten Commandments
Combined figures and words.
- 3 million cycles
- 32 million bytes
- in 2 three-part modules
- twenty-four 8-bit words
Treat ordinal numbers as cardinal numbers
- a second-order relationship
- a third-generation chip
- the 3rd and 12th rows of the matrix
Exercise 1: Each sentence contains at least one error. Correct them.
- I bought 3 computers.
- I bought three computers and 20 printers.
- 10 people came to the meeting at 10 o’clock.
- They have sold four million copies of this software so far.
- The 1st new computer system is ordered already.
- I’ve tried this 2 or 3 times.
- This sentence is 6 words long.
- This increases processing speed by five per cent.
- The screen is 32.56 cm wide and eight cm tall.
- Look in lab number seven.
- Chapter 7 of this book begins on page 1,230.
- The probability of getting this relationship by chance is less than 0.05.
- 2 or three weeks ago that bug was fixed.
- They voted by a 2/3 majority.
- When the result is multiplied by one hundred, you get a percentage.
- The first and tenth lines of the matrix contain 0s
- Two two-part modules were added.
- All of these 8’s have to be written as words.
- Please wait outside Room Seven.
- This chip has a drawing speed of eight ns/pixel with 32 bits per pixel.