Page 42 - Maths Class 03

Checking Addition

To check an addition problem, simply reverse the order of the addends and

add again.

Example : Add 473 and 361 and check.

Solution : 1 1
4 7 3 3 6 1
It is checked in
+ 3 6 1 + 4 7 3
this manner.
8 3 4 8 3 4

When more than two numbers are added together, there is more than one

way to rearrange the addends. The easiest may be to begin with the bottom

and add upward (with the top number being added last). The term “adding
up” comes from an older method in which the sum was written at the top

instead of the bottom.

Know
Know
Know
Get
Get
Get to
to
Addition and subtraction are opposite operations, so you can use one to check the
other. For example, these two facts mean the same thing :

5 + 6 = 11

11 – 5 = 6

Properties of Addition

Let us see some examples of addition.
4 5 6 1
Example : Add 4561 and 4863. + 4 8 6 3

Solution : Add 4561 and 4863 9 4 2 4

Now, add 4863 and 4561.

4 8 6 3
We observe that, 4561 + 4863 = 9424
+ 4 5 6 1
4863 + 4561 = 9424
9 4 2 4

Mathematics-3 42