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Course: MAP Recommended Practice > Unit 43
Lesson 15: Properties of numbersProperties of addition
Explore the commutative, associative, and identity properties of addition.
In this article, we'll learn the three main properties of addition. Here's a quick summary of these properties:
Commutative property of addition: Changing the order of addends does not change the sum. For example, .
Associative property of addition: Changing the grouping of addends does not change the sum. For example, .
Identity property of addition: The sum of and any number is that number. For example, .
Commutative property of addition
The commutative property of addition says that changing the order of addends does not change the sum. Here's an example:
Notice how both sums are even though the ordering is reversed.
Here's another example with more addends:
Associative property of addition
The associative property of addition says that changing the grouping of the addends does not change the sum. Here's an example:
Remember that parentheses tell us to do something first. So here's how we evaluate the left-hand side:
And here's how we evaluate the right-hand side:
Notice that both sides sum to even though we added the and the first on the left-hand side, and we added the and the first on the right-hand side.
Identity property of addition
The identity property of addition says that the sum of and any number is that number. Here's an example:
This is true because the definition of is "no quantity", so when we add to , the quantity of doesn't change!
The commutative property of addition tells us that it doesn't matter if the comes before or after the number. Here's an example of the identity property of addition with the after the number:
Want to join the conversation?
- 2+2+2 = 3+3 Above said this was incorrect selection. Both sides equal 6. The one below has two different answers. Why wouldn't it be this one?(76 votes)
- In the document, It says that how the numbers are grouped does not change the the final answer. This means that while the number stay the same on both sides, the way they are grouped no longer matters.(45 votes)
- This is very simple...
Example:
2+3=3+2
This is the use of the commutative property of addition; for any of you guys who were having trouble.
Now if you want to know how to do the identity property of addition, look at this:
2+0=2
Very easy. :)(31 votes)- I don't know(4 votes)
- I am in 7th grade and this was somewhat easy. but what is the point of properties of addition?(22 votes)
- Properties of addition help make it easier to solve problems. Think of them as a special trick that lets you "break the rules" and simplify the problem.(16 votes)
- Is there a distributive property of addition?(5 votes)
- distributive implies multiplication, so I do not know of any.(5 votes)
- Is there some sort of property that is just plus one (ex: 1+4)?(4 votes)
- None that I have heard of or learned, maybe somewhere else there is, but the Identity Property of Addition is like 16+0, or 10+0(6 votes)
- Why do we need to switch our numbers around when they equal the same thing?(5 votes)
- to make life harder(3 votes)
- which property should I use if I need a balance that's not negative?(5 votes)
- I am in 7th grade and this was somewhat easy. but what is the point of properties of addition?(3 votes)
- I don't know its just addition(2 votes)
- does 0 actually exist?(3 votes)
- This all makes sense, I like it. =)(2 votes)