The student will learn about cardinal and ordinal numbers and their uses in real life. They will get to know about the rules for writing ordinal numbers for class 1 maths and new words related to that.
The discussion in the learning concept is about
- Cardinal numbers
- What is ordinal number
- how to write ordinal numbers
Each concept is explained to students using examples, and illustrations and a concept map are given at the end to summarise the idea. At the end of the page, two printable worksheets with solutions for class 1 maths are attached for students to practice.
Cardinal Numbers
The numbers that give us the exact quantity of an object are called Cardinal numbers. A Cardinal Number says how many of something, such as 1, 2, 3, 4, etc.
Examples: In the following picture, we can use cardinal number to tell the exact quantity of pencils. There are 15 pencils in the given picture. So, 15 is a cardinal number.
Ordinal Numbers
The number which indicates the order or position of an object is called an Ordinal numbers . An ordinal number tells us the position of something in a list. Such as first, second, third, fourth, etc.
Examples: In the given picture, we can use ordinal numbers to indicate the positions of Steve, John, Bella, and Rita.
Steve is standing at 1st position, John at 2nd position, Bella at 3rd position and Rita is standing at 4th position.
- Cardinal numbers tell ‘how many’ of something, they show quantity.
- Ordinal numbers tell the order of how things are set, they show the position or the rank of something.
- Cardinal and ordinal numbers can be memorised as:
Cardinal => counting
Ordinal => Order
How to Write Ordinal Numbers
- When number ends with 1, use the suffix ‘st’.
1st, 21st, 31st, etc.
- When number ends with 2, use the suffix ‘nd’.
2nd, 22nd, 32nd, etc.
- When number ends with 3, use the suffix ‘rd’.
3rd, 23rd, 33rd, etc.
- When number ends with 0, 4, 5, 6, 7, 8 or 9, use the suffix ‘th’.
4th, 14th, 15th, 26th, etc.
Exceptions:
Ordinal numbers for 11, 12 and 13 are 11th, 12th, and 13th, respectively. Ordinal numbers are used in to indicate the position of the object in the line, que or race. There are some other uses of ordinal numbers.
Use of ordinal numbers:
- To indicate the position of an object in a line, in a queue, in a race, etc.
Examples: First in the line, third in the race, 5th in the queue, etc.
- To indicate dates and century.
Examples: 15th August, 21st Century, etc
- To indicate floors/Steps.
Example:
Did you know?
- 25th anniversary of an important event is called as Silver jubilee or ‘Rajat Mahotsav’.
- 50th anniversary of an important event is called as Golden jubilee or ‘Swarn Mahotsav’.
- 75th anniversary of an important event is called as Platinum jubilee or ‘Amrit Mahotsav’.
- 100th anniversary of an important event is called as Centenary or ‘Shatabdi’.
New word:
Suffix: A letter or group of letters added to the end of a word or number to form a derivative. For example; ing, th, etc. Going,Fourth