Page 27 - Viva

Addition
2 Addition

Learning Outcomes
Students will be able to learn:

• addition of numbers (up to 3 digits) with and without carry over.
• place value to add numbers by using standard algorithm.
• to solve problems involving addition in different real life contexts.
• mental computation of sum of 2-digit numbers using different strategies.
• estimation of sum of two numbers and verification by actually computing them.

We already know that the numbers which are added are called addends and the total we
get after addition is called sum.

Addition of Numbers (without carry over)
To add any given numbers, start adding the digits from the ones place and continue moving

towards the left.
Example 1: Add 23 and 45.

Solution: Step 1: Add the ones and write the sum under T O
the ones place. 2 3

3 + 5 = 8 + 4 5
8

Step 2: Add the tens and write the sum under
the tens place. T O
2 3
2 + 4 = 6
+ 4 5
So, the sum of 23 and 45 is 68.
6 8
We can write it as 23 + 45 = 68.

Example 2: Add 431 and 28.
Solution: Step 1 Step 2 Step 3

H T O H T O H T O

4 3 1 4 3 1 4 3 1
+ 2 8 + 2 8 + 2 8

9 5 9 4 5 9

So, 431 + 28 = 459.

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