1. MEANING OF PROPERTIES OF ADDITION
State the meaning of addition
Identity the properties of addition
Apply the properties of addition in performing the operation
Notice that we added the numbers two by two. This can be
done because addition is a binary operation;that is, we can add
only 2 numbers at a time. Also, in finding the number of animal,
we made use of some properties of addition. Some of these are
as follows:
1. Commutative Property of Addition (CPA)
The commutative or order property of addition states that
the order of the addends does not change the sum.
Example: 52 + 28 = 80 So, 52 + 28 = 28 + 52
To understand or remember this, think of having 52
rubber bands in one bunch and 28 in another bunch. You
want to put them in a box. Does it matter whish bunch you
put in the box first?
2. Associative Property of Addition (APA)
The associative property of Addition states that the
numbers to be added are grouped does not affect the sum.
Example: (15 +45) + 28 15 + (45 + 28)
= 60 = 15 + 73
= 60 + 28 = 88
2. = 88
Thus, (15 + 45 ) + 28 = 15 + ( 45 + 28 )
3. Identity Property of Addition (IPA)
The identity or zero property of additionstates that the
sum of a number and zero is equal to the number. Zero is
called the identity element for addition.
Examples: 75 + 0 = 75 0 + 93 = 93
Sometimes, the commutative and associative properties of addition
help us do addition mentally or in an easier way. By using these
properties, we can rearrange the addends to form a sum which is a
multiple of 10 or 100. Then, we can add remaining number.
Examples:
1. 14 + ( 15 + 6 )
= 14 + ( 6 + 15 ) Commutative Property of Addition (CPA)
= (14 + 6 ) + 15 Associative Property of Addition (APA)
=20 + 15
= 35
2. 81 + (24 + 19)
= 81 + (19 + 24) Commutative Property of Addition (CPA)
= (81 + 19) + 24 Associative Property of Addition (APA)
= 100 + 24
3. =124
The examples have been given in detail but practice,
you can do much of the work mentally. You not write all the
steps once you know how to do it.
Example: 43 + 53 + 37
= 80 +53
= 133
Do you see how it was done? Yes, 43 and 37 were added to
get 80. Then, 53 was added to 80 to get 133.
