# Cardinal and ordinal numbers

## Types of numbers

Numbers are divided into two categories. **Cardinal numbers** that we use to determine the amount and quantity of something. And **ordinal numbers** that we use to determine the order, the position, or the rank of something.

In this lesson you will learn how you can read and write cardinal and ordinal numbers from zero to billion.

### Difference between ordinal and cardinal numbers

The main difference between them is that cardinal numbers are read as **one**, **two**, **three** and they written as 1, 2, 3. While ordinal number are read as **the first**, **the second**, **the third** and they written as 1^{st}, 2^{nd}, 3^{rd}.

## Cardinal numbers

To count perfectly in English, you shoud know how to count from **0** to **19** and the rest will be easy. Notice that numbers from 13 to 19 are same as numbers fro 3 to 9 with the suffix **teen**.

0 Zero

1 One

2 Two

3 Three

4 Four

5 Five

6 Six

7 Seven

8 Eight

9 Nine

10 Ten

11 Eleven

12 Twelve

13 Thirteen

14 Fourteen

15 Fifteen

16 Sixteen

17 Seventeen

18 Eighteen

19 Nineteen

### The tens

Tens from twenty to ninenty are always end by **ty**.

20 Twenty

22 Twenty-two

30 Thirty

33 Thirty-three

40 Forty

44 Forty-four

50 Fifty

55 Fifty-five

60 Sixty

66 Sixty-six

70 Seventy

77 Seventy-seven

80 Eighty

88 Eighty-eight

90 Ninety

99 Ninety-nine

### The hundreds

Hundreds are each number itself followed by the word **hundred**.

100 One hundred

200 Two hundred

300 Three hundred

400 Four hundred

500 Five hundred

600 Six hundred

700 Seven hundred

800 Eight hundred

900 Nine hundred

### Big numbers

We write every number followed by its class like **thousand**, **million** and **billion**.

1000 One Thousand

3000 Three Thousand

1000000 One Million

5000000 Five Million

1000000000 One Billion

8000000000 Eight Billion

## Ordinal numbers

To learn ordinal numbers, you should know first how to count form **1** to **19** and the rest will be repetitive. Ordinal numers are the same numbers ending by **th** except the numbers 1, 2 and 3.

1 First

2 Second

3 Third

4 Fourth

5 Fifth

6 Sixth

7 Seventh

8 Eighth

9 Ninth

10 Tenth

11 Eleventh

12 Twelfth

13 Thirteenth

14 Fourteenth

15 Fifteenth

16 Sixteenth

17 Seventeenth

18 Eighteenth

19 Nineteenth

### Ordinal tens

Ordinal tens from 20 to 90, are the same numbers but the **y** letter at the end is transfotrmed into **tieh** if the position of ones is zero. If was not we write the tens, then the ones are written as ordinal.

20 Twentieth

22 Twenty-second

25 Twenty-fifth

30 Thirtieth

31 Thirty-first

34 Thirty-fourth

40 Fortieth

41 Forty-first

44 Forty-fourth

50 Fiftieth

53 Fifty-third

55 Fifty-fifth

60 Sixtieth

62 Sixty second

66 Sixty-sixth

70 Seventieth

71 Seventy-first

77 Seventy-seventh

80 Eightieth

83 Eighty-third

88 Eighty-eighth

90 Ninetieth

91 Ninety-first

99 Ninety-ninth

### Ordinal Hundreds

Ordinal Hundreds are written as a normal number followed by the word **hundredth**.

100 hundredth

200 Two hundredth

300 Three hundredth

400 Four hundredth

500 Five hundredth

600 Six hundredth

700 Seven hundredth

800 Eight hundredth

900 Nine hundredth

### Big Ordinal Numbers

We add **th** at the end to big classes like **thousand**, **million** and **billion**.

1000 Thousandth

3000 Three Thousandth

1000000 Millionth

5000000 Five Millionth

1000000000 Billionth

8000000000 Eight Billionth

### Abbreviations

We can use a short way to write ordinal numbers. Simply write the digit form of number with last two letters.

1 1st

2 2nd

3 3rd

4 4th

5 5th

6 6th

7 7th

8 8th

9 9th

10 10th

11 11th

12 12th

13 13th

14 14th

15 15th

16 16th

17 17th

18 18th

19 19th

20 20th

21 21st

22 22nd

23 23rd

24 24th

25 25th

30 30th

40 40th

55 55th

90 90th

99 99th

100 100th

101 101st

152 152nd

999 999th

1000 1000th

1001 1001st

1500 1500th

1000000 1000000th

1000001 1000001st

1500000 1500000th

## Fractions

**Fraction** is numerical value that is a part of a whole. We read **the numerator** (upper part) as a cardinal number and **the denominator** (lower part) as a ordinal number.

Here are some fractions:

1/2 Half or one half

1/3 One third

1/4 Quarter or one quarter

1/6 One sixth

We add an **s** to the lower number if the upper part was bigger than 1.

2/5 Two fifths

3/4 Three quarters

4/7 Four sevenths

7/8 Seven eighths

## How to read numbers?

You should know that the way people read numbers is usually brief and we will mention them to you.

### Years Numbers

Usually we group names of years into two sets of two digits.

Here are some examples:

1994 Nineteen ninety-four

2020 Twenty twenty

### Units and Currencies

We read numbers that used to indicate currencies as usual. We add an **s** if the used number was bigger than 1.

Here are some examples:

$1 One dollar

$50 Fifty dollars

€30 Thirty euros

10m Ten meters

5L Five litters

20kg Twenty kilograms

### Decimal Numbers

Decimal numbers are numbers that contain a **decimal point**.

Here are some examples:

$0.05 Five cents, or zero point zero five dollar

$9.99 Nine ninety-nine, or nine dollars and ninety-nine cents

€3.30 Three thirty, or three euros and thirty cents

### Other ways to read numbers

If the decimal number starts by a zero, we should say **point** then the numbers after it.

Here are some examples:

0.05 Point zero five

0.75 Point seventy-five, or point seven five

### Phone numbers

When reading phone numbers, we read the number **0** as the **letter O**.

0096170440102 o o nine six one seven o four four o one o two

We can use the words **double** and **triple** if numbers are repeated like the following.

004955507 double o four nine triple five o seven