Numbers

(1) Introduction

In business and technical writing, numbers form a major part of our written texts. Therefore, it is important to bear in mind a few elementary rules of style, which will help to ensure both consistency and clarity when using written numbers.

  • Numbers below ‘ten’ should be written out in words. There are, however, two exceptions to this rule:
    1. page numbers
    2. units of measurement
    There are three ways to generate revenue
    Page 6 outlines the main steps that need to be taken
    The device has a 4-inch screen and weighs only 9 ounces
  • If a sentence begins with a number, write out the number in words:
    Thirty-five people have been interviewed for the position of CFO this month
  • If this feels awkward or unnatural, then revise the sentence:
    This month we have interviewed 35 people for the position of CFO
  • If you need to use lots of complex numbers, put them in list-form to make them easier to read, for example:
    1. 2691
    2. 4378
    3. 1892
    4. 6581
  • Use the following convention when you write dates. Be consistent in using it:
    Until the 7th of May 2010 the supply of bananas will be uncertain in some areas

(2) Cardinal and Ordinal Numbers

Numbers that express quantity, “three secretaries”, “500 branches” are written and pronounced as ‘cardinal numbers’ (see left of chart below). When you need to express the sequence or order of an event, remember to use ‘ordinal numbers, (see right of chart below). We use ordinal numbers for dates*, comparative results, gradings and league tables. (*for variations of date-writing styles, see below)

Cardinal
Ordinal
1
One
1st
First
2
Two
2nd
Second
3
Three
3rd
Third
4
Four
4th
Fourth
5
Five….
5th
Fifth
11
Eleven
11th
Eleventh
12
Twelve
12th
Twelfth
13
Thirteen
13th
Thirteenth
14
Fourteen
14th
Fourteenth
15
Fifteen
15th
Fifteenth
20
Twenty
20th
Twentieth
21
Twenty-one
21st
Twenty-first
22
Twenty-two
22nd
Twenty-second
30
Thirty
30th
Thirtieth
40
Forty
40th
Fortieth
50
Fifty
50th
Fiftieth
60
Sixty
60th
Sixtieth
70
Seventy
70th
Seventieth
80
Eighty
80th
Eightieth
90
Ninety
90th
Ninetieth
100
One hundred
100th
One hundredth

Exercise (see answers below)
Write down the following numbers:

a. The thirtieth of June
b. Three point one four two
c. Four oh six, three double-nine
d. One thousand two hundred and three
e. Nineteen thirty-nine
f. Ninety
g. The nineteenth century
h. Seven and a half percent
i. Eleven forty five
j. Four thousand nine hundred and two

Answer key:
a. the 30th of June b. 3.142 c. 406399 d. 1,203 e. 1939 f. 90 g. the 19th century h. 7.5% i. 1145 j. 4,902

(3) Writing Dates

European and American styles of date writing are quite different and you need to pay attention in order to avoid confusion in transatlantic communication:

  • In the US, the 1st day of April is written as 4/1/2010.
  • To a European, this looks like the 4th day of January.
  • The Americans place the month before the day.
  • In Europe, April Fools Day is written as 1.4.2010.
  • To avoid this confusion, write out the date as April 1st 2010.

(4) Prefixes expressing numbers

Here are two lists of prefixes expressing numbers. One list comes from Latin and the other from Greek. What words do you know that begin with these prefixes?

No.
Latin
Greek
Meaning
1
Uni
Mono
One
2
Bi
Di
Two
3
Tri
Tri
Three
4
Quart
Tetra
Four
5
Quint
Penta
Five
6
Sex
Hexa
Six
7
Sept
Hept
seven
8
Oct
Oct
Eight
9
Non
Ennea
Nine
10
Dec
Dec
Ten
11
Cent
Hecto
Hundred
12
Mil
Kil
Thousand
13
Semi
Hemi
Half

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