What Are Ordinal and Cardinal Numbers?
Be it indicating the order in a sequence or the ranking of someone’s favorite sports team, numbers are used for different purposes. To make them easier to use, numbers are divided into two categories, ordinal numbers and cardinal numbers.
Ordinal numbers show the place value of something. They can be whole numbers, fractions, or decimals. Cardinal numbers, on the other hand, are numbers that are used for quantification purposes. They are whole numbers that aren’t decimals or fractions and are used for counting.
Ordinal Numbers Usage
Ordinal numbers are written in two ways:
| Ordinal Numbers (Spelled Out) | Ordinal Numbers (Abbreviated) |
| First | 1st |
| Second | 2nd |
| Third | 3rd |
| Fourth | 4th |
| Fifth | 5th |
| Sixth | 6th |
| Seventh | 7th |
| Eighth | 8th |
| Ninth | 9th |
| Tenth | 10th |
These numbers are used both in writing and in speech. In writing, numbers are spelled out or abbreviated. In case of double digits, a hyphen should be used in between the two numbers.
Below are some common uses of ordinal numbers.
1. Sequence or Order
Ordinal numbers are used to indicate place, rank, or position of something in a sequence.
Here are some example sentences:
- Can you please turn off the projector? It’s the third switch from the left.
- My daughter was the first to reach the marathon finish line.
- Our company ranked fifth in Forbes’ World’s Best Employers’ survey.
- We will be flying first-class for the fourth time.
- Louis the Fourteenth, also known as Louis the Great, was one of the most influential French rulers in the history of France.
2. Fraction
The denominator in a fraction is written using ordinal numbers. Also, while spelling out mixed fractions, the conjunction “and” should be used between the whole number and the fraction.
Here are some examples of ordinal numbers used in fractions:
- 1/3 → one third
- 9 3/4 → nine and three fourths.
- 2/5 → two fifths
- 8/10 → eight tenths
- 5 1/3 → five and one thirds
3. Dates
Ordinal numbers are either spelled out or abbreviated when writing dates. When days are spelled out, the years are mostly written in numbers.
Here are examples showing how ordinal numbers are used to write dates:
- What plans for the Fourth of July?
- My birthday is on the tenth of this month.
- Their wedding anniversary is on the 27th of September.
- We need to complete the project by the 7th of this month.
- I’m leaving for Boston on the 12th of next month.
4. Address
It’s common to come across numbers in addresses, and these numbers are sometimes a combination of cardinal and ordinal numbers or just ordinal numbers. Irrespective of the type of number used while writing an address, ordinal numbers are used while speaking. When spelling out an address, it is important to use proper punctuation. A hyphen is used to separate two numbers.
Below are some examples:
- John lives on sixty-seventh street.
- The office building is on 9th Avenue.
- We moved to thirty-second street recently.
- The florist is on 3rd Avenue.
- The veterinarian lives on ninety-fourth street.
5. Time
Similar to dates, it is common to use ordinal numbers in case of time and time periods as well.
Following are some examples:
- Several inventions that are benefiting mankind were made in the 19th century.
- This is our third-year anniversary.
- This is my 7th year working for the Obama administration.
- The POTUS completed his first term successfully.
- The internet is one of the greatest inventions of the 20th century.
Cardinal Numbers Usage
Cardinal numbers are used every day to count or quantify. While writing cardinal numbers, it’s important to use proper punctuation. A hyphen is used between two numbers while spelling out compound numbers. Also, it’s important to use commas to separate numbers to show proper decimal places.
Cardinal numbers are written in two ways:
| Cardinal Numbers (Spelled Out) | Cardinal Numbers |
| One | 1 |
| Four | 4 |
| Ten | 10 |
| Fifteen | 15 |
| Nineteen | 19 |
| Twenty-five | 25 |
| One hundred and two | 102 |
| Five hundred and nine | 509 |
| One thousand | 1,000 |
| One thousand three hundred and thirty two | 1,332 |
Below are some sentences that show how cardinal numbers should be written.
- There are three dogs in the shelter that are available for adoption.
- Amanda is 15 years old.
- Joanne has four cats at home.
- The recipe specifies using two pounds of yam.
- My parents live 20 miles away from my place.
Note: In English, numbers below ten are usually spelled out while all other numbers are written in digits.
A lot of non-native English speakers and learners find it difficult to properly use ordinal numbers and cardinal numbers. Understanding the difference between ordinal numbers and cardinal numbers and how to use them while speaking and writing is crucial to improving one’s language skills.
