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Last updated on 13 September 2025
We often describe the position of various objects, people, or places using words such as 1st, 2nd, 3rd, and so on. These are known as ordinal numbers. Ordinal numbers are used to represent the rank of people or objects. For example, Annie is ranked 3rd in her school. Let’s now learn about ordinal numbers in detail.
Ordinal numbers are used when we want to represent an object’s rank or position in relation to other objects. For instance, 1st is the ordinal form of the number 1.
Suppose you want to list the positions of students in a class based on their test scores. The positions would be:
1st, 2nd, 3rd, etc.
To write ordinal numbers, add the appropriate suffix to the base cardinal number . The most commonly used suffixes are -st, -nd, -rd, or th, based on the number.
It often follows the form: Ordinal Number = Cardinal Number + Suffix
For example, 2 + nd = 2nd.
The term ordinality refers to the position or rank of an object in a sequence. Ordinality determines the order in which something is placed in a list or sequence. For example, the order of numbers in the set {1, 2, 3, 4} is described as first, second, third, and fourth.
Do not confuse this with cardinality, which indicates the size or quantity of objects in a sequence.
Ordinal, cardinal, and nominal numbers are different numerical representations of the position, quantity, or classification of different objects. Understanding their differences will help you familiarize yourself with the concepts:
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Ordinal Numbers |
Nominal Numbers |
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Ordinal numbers are largely utilized in representing the position, rank, or order of things. Here are a few real-life applications of ordinal numbers:
Students often make mistakes when trying to position, rank, or label objects. Here are a few common mistakes and ways to avoid them:
In a 200-meter race, Sam finished after three other runners. What is Sam’s position?
4th place.
Since Sam finished after three other runners, we can conclude that he is in 4th place.
Juan turns 12 this week. How should he write it in ordinal form?
12th birthday.
The ordinal form of 12 is 12th. So, we write, Juan is celebrating his 12th birthday this week.
Leona lives five floors above the first floor. Write the ordinal form for her floor.
6th floor.
Since the ground floor is considered the first floor, Leona is on the 6th floor.
Aldo holds the rank of number 2 in his school. How should we express this in ordinal form?
2nd rank
We write the number 2 in ordinal form as 2nd, so we say: Aldo holds the 2nd rank in his school.
Ben, Jake, Peter, and Rio are the top four students in the class respectively. How should we express their positions in ordinal form?
Ben secured 1st place, Jake 2nd, Peter 3rd, and Rio 4th, representing their positions in ordinal form.
The top four cardinal numbers are 1, 2, 3, and 4. So to express them in ordinal form, we add suffixes based on the number’s ending digit.
Hiralee Lalitkumar Makwana has almost two years of teaching experience. She is a number ninja as she loves numbers. Her interest in numbers can be seen in the way she cracks math puzzles and hidden patterns.
: She loves to read number jokes and games.