What are Ordinal Numbers?
Ordinal numbers are defined as numbers that represent a certain rank or position of an object or a person or of anything that is arranged in an order. In other words ordinal numbers describe the order in which objects or people are placed or located.
Ordinal numbers are used for positioning or ranking numbers for various parameters such as weight, height, marks, size, and so on.
How do we write Ordinal Numbers?
Ordinal numbers are generally expressed by using numerals as prefixes and the corresponding adjectives as suffixes. For example, 1st, 2nd, 3rd, 4th, 5th, 6th, 7th, 8th, 9th, and the ordinals continue in this order. As you can see, the first part of the ordinal number consists of a number, and the suffix expresses the positioning parameter.
Ordinal numbers can also be written as first, second, third, and so on.
Let’s understand this with an example:
If the students of your class participate in a math olympiad then the student with highest score will be ranked 1st or first, the student with the second highest score will be ranked 2nd or second and the student with the third highest score will be ranked third or 3rd.
Here, 1st or first, 2nd or second and 3rd or third, are ordinal numbers.
List of ordinal numbers
The following list consists of ordinal numbers from 1 to 100.
Solved Examples
Example 1: Find the position of the green square in the following image.
Solution:
There are five squares of different colors, as we can see from the image.
Now, we have to find out the position of the green square.
So, if we move from left to right, starting with the red square, by counting, we observe that the green square is in the third position.
So, the ordinal number for the green square is 3rd.
Example 2: In the word ‘ALLIGATOR’, which is the fifth letter?
Solution:
Let us first count the letters in the word ‘ALLIGATOR’. As you can see, there are 9 letters in the word. Now, we have to find the fifth letter.
A L L I G A T O R
Counting from the left to the right, the fifth letter is G.
Hence, the fifth letter is ‘G’ in the word, ‘ALLIGATOR’.
Example 3: Amelia, Tiffany, Leslie, and Patricia are waiting in a queue outside their school library. Who is standing in the third position?
Solution:
As stated in the question, the children are standing in a queue. So, we can say that Amelia is in first place, Tiffany is in second place, Leslie is in third place, and Patricia is in fourth place in the queue.
Thus, Leslie is standing in the third or 3rd position.
No, 0 is not an ordinal number as the positioning of 0 cannot be done.
Ordinal numbers are useful for ordering objects or people. These numbers are helpful when data is provided and the data needs to be arranged in order.
While cardinal numbers express the count of numbers of objects, ordinal numbers express the position of the objects. For example, 1, 2, and 3 are cardinal numbers but then, 1st, 2nd, and 3rd are ordinal numbers.
Ordinal numbers were discovered by Georg Cantor in 1883.