A cardinal number is such a number that is used to express the quantity of an item. An ordinal number is used to define a thing’s place or position in a particular list.
Cardinal Numbers
A Cardinal number is used as a noun within a sentence. A cardinal number is such a number that is used to express the quantity of an item. Whenever you hear the word ‘cardinal number’, think ‘how many’ because it tells you how many of something there exists.
For example,
- One
- Two
- Three
- Four
- Five
- Six
- Ten
- Eighteen
- Sixty-two
A Few Example Sentences using Cardinal Numbers
1. We have only five glasses.
2. Tomorrow is my sister’s birthday. She will turn 18.
3. You have asked to bring 100 colorful balloons.
4. Girl at the number 14 is amazing and very talented.
5. Let me introduce these four volunteers.
Ordinal Numbers
An ordinal number is used as a noun within a sentence. It is such a number that is used to define a thing’s place or position in a particular list.
For example,
- 1st > first
- 2nd > second
- 3rd > third
- 4th > fourth
- 22nd > twenty-second
- 57th > fifty-seventh
A Few Example Sentences using Ordinal Numbers
1. This Saturday, she will celebrate her fiftieth birthday.
2. It is time to show my ninth dress.
3. She stood first in the class.
4. I am not designed to come second or third. I am designed to win. (Ayrton Senna)
5. Are you the seventh candidate in the list?
An Important Point
According to AP Style, you should not abbreviate the numbers from one to nine. The whole word should be written out i.e. one, two, three, four, five, six, seven, eight, and nine.
However, other than the numbers one to nine, all the other cardinal numbers should be abbreviated (i.e. in a numerical form).
For example,
1. You need to buy only one notebook for the notes. (Correct)
• You need to buy only 1 notebook for the notes. (Wrong)
2. There are only 15 papers left. (Correct)
• There are only fifteen papers left. (Wrong)
All the ordinal numbers, on the other hand, should not be abbreviated in writing. They should be spelled out.
For example,
1. This is the third time that I am repeating this question. (Correct)
• This is the 3rd time that I am repeating this question. (Wrong)
2. Let us play the sixteenth track on the list. (Correct)
• Let us play the 16th track on the list. (Wrong)
Note: However, there are exceptions to these rules. For example, you can use the figure (i.e. the numerical forms) in writing addresses or ages etc. Click on AP Style Numbers to learn more about the rules.
Contextual Use Cases
Cardinal and ordinal numbers are commonly used in various real-world contexts to express quantities and positions. Below are a few examples of how they function in everyday situations:
1. Time and Dates
Ordinal numbers are essential for expressing dates, marking specific days, months, or years. They help identify the sequence of events or periods in history.
- Example: “The Declaration of Independence was signed on July 4th, 1776.”
- Example: “The 21st century has seen rapid technological advancements.”
2. Quantities in Shopping or Inventory
Cardinal numbers are frequently used to count items, especially in shopping or inventory management, where the exact number of objects is important for organization and planning.
- Example: “We need to order 50 chairs for the conference.”
- Example: “The store has only three bottles of milk left in stock.”
By using cardinal numbers to express quantities and ordinal numbers to describe positions or dates, we can effectively communicate important information in various contexts.
What Did You Learn?
Cardinal number expresses the quantity of something, for example, one, two, three, four, eighteen, sixty-two, etc. An ordinal number, on the other hand, defines a thing’s place in a list, for example, first, second, third, fourth, fifth, etc.