How Many? (Addition and Subtraction of Single Digit Numbers) Class 1 Notes Maths

What is Addition? 

• Counting things together is called addition.
• The words total, sum, add, more, in all, altogether etc., mean addition.
• The symbol for addition is +, read as plus.
• The answer we get by adding two numbers is called sum.

Addition by Counting Forward

EduRev Tips: It is easy to add if we start from the bigger number while doing addition by counting forward.

How Many Altogether?

Addition of Two Single Digit Number

Horizontal Addition

Example 2:

Vertical Addition

Example 2:

Adding 0 to a number

When we add 0 to a number, the sum is the number itself. 

Add and Match

Let's match it:

Writing the Missing Numerals

What is Subtraction?

Take Away

• There are 8 carrots in the basket. A rabbit takes away 3 carrots. How many carrots are left in the basket now?
  
• To find how many carrots are left, we cross out 3 carrots and count the remaining uncrossed carrots.
  
• There are 5 uncrossed carrots.
  So, 5 carrots are left in the basket.
  We can write it as:
  8 - 3 = 5 Or 

EduRev Tips: When we write the smaller number below the bigger number for subtraction,
it is called vertical subtraction.

Pictorial and Numerical subtraction

• Four little dicky birds sitting on a tree, one flew away and then they were

• Three little dicky birds sitting on a tree, one flew away and then they were

• Two little dicky birds sitting on a tree, one flew away and then they were

• There are two ways of writing a subtraction problem.
  

Subtraction

Here, we count the flowers given before the sign of minus and after the sign of minus. We subtract it through the normal method of subtraction.

This can be further written as:

Or,

Writing the Missing Numbers

Example 2: