Subtraction up to 9 Chapter Notes | Mathematics Class 1 ICSE PDF Download

What is Subtraction?

Subtraction means taking away.

• We start with a group, remove some items, and count what’s left.
• The symbol is “–” called minus.
• The answer is called the difference.
• Example: 4 – 2 = 2
• Read “four minus two equals two.”

Here are some more examples:

Subtracting Zero or the Same Number 

Subtracting Zero (– 0):

• Imagine you have 5 apples in a basket. If you don’t take any away (you remove zero), you still have all 5 apples.
• That’s why 5 – 0 = 5.
• Remember: “Take away nothing, keep everything!”

Here are some more examples:

Subtracting the Same Number (– itself):

• Now imagine you have 3 cookies and you give all 3 away. You took away exactly what you had.
• After giving away 3 cookies, you have 0 left.
• That’s why 3 – 3 = 0.
• Remember: “Take away all, nothing remains!”

Here are some more examples:

Subtraction on a Number Line 

To subtract on a number line, we move backward.

• Draw a line from 0 to 9.
• To subtract, start at the first number and jump backward the second number of steps.

Example 1: 8 – 5 = ?

• Start at 8.

• Jump back 5 steps → land on 3.

• So, 8 – 5 = 3.

Example 2: 7 – 1 = ?

• Starting from 7 
• We count back 1. 
• We get the answer 6.

Vertical Subtraction 

• Write the larger number on top, the smaller directly below, lining up ones.
• Subtract down the column.

Here are some examples: 

Word Problems

Question 2: There were 5 apples. Sam ate 2 apples. How many are left?”
Ans: 5 – 2 = 3 → There are 3 apples left.