Page 19 - SM Class 4 Inner.cdr

Example 6 : Find the sum of 669702, 154789 and 113465.
Arrange the digits of the addends in columns L TTh Th H T O
and add as usual. 1 1 1 1 1 1
The sum is 937956. 6 6 9 7 0 2
+ 1 5 4 7 8 9
+ 1 1 3 4 6 5
9 3 7 9 5 6

Properties of Addition

Order Property of Addition

We can add two numbers in any order. The sum remains the same. This

property is also called commutative property.

Example 7 : Find the sum of 460721 and 237544.
Solution : L TTh Th H T O L TTh Th H T O

4 6 0 7 2 1 2 3 7 5 4 4

+ 2 3 7 5 4 4 Or + 4 6 0 7 2 1
6 9 8 2 6 5 6 9 8 2 6 5
In both cases, the sum remains the same.

Additive Property of Zero

If zero is added to a number, the sum is the number itself. Zero is called
additive identity.

Example 8 : Add 423456 and 0.
Solution : L TTh Th H T O

4 2 3 4 5 6
+ 0
4 2 3 4 5 6

The sum is the number itself.

Grouping Property of Addition

While adding three or more numbers we may group the numbers in any order.

The Sum remains the same. This is also called grouping property of addition.

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Mathematics In Focus - 4