Ordinal Numbers

Introduction to Ordinal Numbers

Ordinal numbers are representations of numbers used to describe the position or order of objects. Ordinal Numbers help us indicate where something is located in a sequence. For example, when we say, “The candies are in the 4th drawer from the top,” or “The black dress is the 9th one from the right,” we’re using ordinal numbers to specify the position of these items.

In this article, we will study Ordinal Numbers, the list of Ordinal Numbers, examples and more.

What Are Ordinal Numbers?

Ordinal numbers are used to indicate the position or rank of something in a sequence. Unlike cardinal numbers that tell us “how many,” ordinal numbers tell us “which one” in an ordered set. They show the order or ranking of items based on criteria like size, importance, or sequence.

For example, if we consider a contest with ten participants. The top three winners are ranked 1st, 2nd, and 3rd. These positions are ordinal numbers. They tell us the specific place of each student in the order of their performance.

Also Check: Cardinal and Ordinal Numbers

List of Ordinal Numbers from 1 to 100

Below is the list of ordinal numbers from 1 to 100, showing their corresponding names:

Points to be Noted:

• Ordinal numbers for 1 through 3 use “st,” “nd,” and “rd,” respectively.
• For numbers 4 and beyond, use “th”.

Ordinal Numbers from 1 to 20

Ordinal numbers from 1 to 20 each have unique names. Here’s the list of Ordinal numbers from 1 to 20:

1st: First

2nd: Second

3rd: Third

4th: Fourth

5th: Fifth

6th: Sixth

7th: Seventh

8th: Eighth

9th: Ninth

10th: Tenth

11th: Eleventh

12th: Twelfth

13th: Thirteenth

14th: Fourteenth

15th: Fifteenth

16th: Sixteenth

17th: Seventeenth

18th: Eighteenth

19th: Nineteenth

20th: Twentieth

Pattern Beyond 20

After 20, ordinal numbers follow a repeating pattern with the addition of “st,” “nd,” “rd,” or “th” based on the last digit of the number, but with specific exceptions for numbers ending in 11, 12, and 13. For example:

21st: Twenty-First

22nd: Twenty-Second

23rd: Twenty-Third

This pattern continues similarly for higher numbers, making it easier to determine the ordinal number for numbers beyond 20.

Also Check: Counting Numbers

How to Write Ordinal Numbers

Ordinal numbers are written by combining numerals with suffixes to indicate position or order. Here’s how they are typically written:

1st: First

2nd: Second

3rd: Third

4th: Fourth

5th: Fifth

6th: Sixth

7th: Seventh

8th: Eighth

9th: Ninth

10th: Tenth

How to Identify and Use Ordinal Numbers

Ordinal numbers indicate the position or rank of something in a sequence. They are written with numerals followed by specific suffixes:

• For 1, 2, 3: Use “st,” “nd,” and “rd,” respectively (e.g., 1st, 2nd, 3rd).
• For other numbers: Use “th” (e.g., 4th, 5th, 6th, 11th, 12th).

Applications of Ordinal Numbers

Ordinal numbers are useful for describing the order or rank of items in a sequence. Here are some key applications:

• Ordinal numbers are commonly used to rank individuals or items. For example, in a competition, participants might be ranked 1st, 2nd, or 3rd based on their performance. This helps in identifying the winner, runners-up, and those with lower rankings.
• Ordinal numbers help to indicate the sequence of events or milestones. For instance, you might refer to the “1st day of the month,” “2nd quarter of the year,” or “3rd stage of a project” to specify the exact point in time or phase of a process.
• When data is arranged in a specific order, ordinal numbers help in sorting and categorising the data. This is useful for creating lists, organising results, or presenting information in a structured manner.

Visual Example of Ordinal Numbers

Consider a 500-meter race. The positions of the athletes are indicated by ordinal numbers:

1st: The winner of the race.

2nd: The runner-up.

3rd: The third-place finisher.

By using ordinal numbers, we clearly understand the ranking of each athlete and identify who finished in which position.

Difference Between Cardinal and Ordinal Numbers

Cardinal and ordinal numbers are different from each other. Below discussed are the differences between Ordinal Numbers and Cardinal numbers.

Cardinal Numbers

Cardinal Numbers indicate the count or quantity of objects. Examples include 1, 2, 3, and so on. For instance, if we say, “There are 3 ants and 5 bears,” the numbers 3 and 5 are cardinal numbers because they tell us how many ants and bears there are.

Ordinal Numbers

Ordinal Numbers indicate the position or rank of objects in a sequence. Examples include 1st, 2nd, 3rd, etc. For example, if we say, “The position of the runners in the running event is first, second, third,” these are ordinal numbers because they show the ranking of the runners.

Difference Between Ordinal Numbers and Nominal Numbers

Ordinal Numbers and Nominal Numbers are different from each other. Below discussed are the differences between them.

Ordinal Numbers

Ordinal numbers are used to indicate the position or rank of items in a sequence or hierarchy. They help in ordering items, such as ranking participants in a race (1st place, 2nd place) or specifying the position of a house on a street (e.g., “34th house”). Operations such as addition or subtraction are meaningful with ordinal numbers in terms of comparing ranks (e.g., the difference between 1st and 3rd place).

Examples: 1st, 2nd, 3rd, 4th, etc.

Nominal Numbers

Nominal numbers are used for labelling or identifying items without implying any quantitative value or order. They provide a unique identifier. They are used to distinguish items or entities, such as identifying a specific phone line or vehicle, but do not convey information about the position or rank. Mathematical operations such as addition, subtraction, multiplication, or division are not meaningful with nominal numbers. They serve purely as labels.

Examples: Phone numbers, vehicle registration numbers, area codes (e.g., 202 588-6500).

Solved Examples of Ordinal Numbers

1. Which English alphabet is 12th from the beginning?

Ans. To find the 12th letter from the beginning of the English alphabet we will observe the alphabetical sequence.

The alphabet sequence is A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V, W, X, Y, Z.

Therefore, the 12th letter is L.

2. Kim, Kethy, Kiah, and Kaina are sitting in line in alphabetical order. What is the position of Kiah from the beginning?

Ans. Arrange the names alphabetically:

Alphabetical order: Kaina, Kethy, Kiah, Kim.

Kiah is in the 3rd position.

3. Christmas lies on the _____ of December.

Ans. Christmas is celebrated on the 25th of December.

Practice Questions of Ordinal Numbers

1. What is the 8th letter in the English alphabet?
2. Sarah, Emily, Mia, and Olivia are standing in line according to their height, with Sarah being the shortest and Olivia being the tallest. If Emily is taller than Mia but shorter than Sarah, what is Emily’s position from the beginning?
3. The 15th book in a series is titled “The Secret Adventure.” What is the title of the book that is 15th in the series?
4. In a queue of people, John is 5th from the front, and Alice is 10th from the back. How many people are in the queue?
5. On a race track, the runners finished in the following order: 1st place: Tom, 2nd place: Jerry, 3rd place: Alex, and 4th place: Sam. If Sam finished ahead of Jerry but behind Tom, what is the correct order of runners?
6. The concert starts on the 3rd day of the month. If today is the 15th, how many days ago did the concert start?
7. The 7th month of the year is represented by the ordinal number 7. What month is it?
8. A group of friends is standing in a line. If Jason is 4th from the end and Liam is 3rd from the start, how many friends are in the line if Liam is standing directly in front of Jason?

FAQs on Ordinal Numbers

What is cardinal and ordinal numbers?

Cardinal numbers are numbers that represent quantity. They answer the question how many? For example, when you say three apples, the word three is a cardinal number because it indicates the count of apples. On the other hand, ordinal numbers indicate position or order in a sequence. They answer the question which one? For instance, in the phrase the third apple, the word third is an ordinal number because it shows the apple's position in a list.

What is a cardinal number called?

A cardinal number is simply referred to as a cardinal. It is used to denote the size of a set or the count of items within that set. Cardinal numbers include whole numbers like one, two, three, and so forth, and they can be used in both singular and plural forms depending on the context.

Which comes first ordinal or cardinal?

The primary difference between cardinal and ordinal numbers lies in their purpose. Cardinal numbers are used for counting, while ordinal numbers are used to indicate rank or order. For example, in a race, the first, second, and third places are described using ordinal numbers, while the total number of participants would be described using cardinal numbers. In terms of sequence, cardinal numbers typically come first in counting, followed by ordinal numbers when discussing the order of items. For example, you might first count the items (cardinal) and then rank them (ordinal).

What is an example of a cardinal number?

An example of a cardinal number is seven, as in There are seven books on the shelf. This indicates the total number of books without implying any order.

When to use cardinal numbers?

Cardinal numbers are used when you need to express quantity, such as counting objects, people, or events. They are commonly used in everyday situations, such as when shopping, measuring, or tallying scores in games. In contrast, ordinal numbers are used when you need to describe the position of something in a list or sequence, such as ranking contestants in a competition or indicating the date in a calendar.