Factor Pairs
Factor pairs are two numbers that you can multiply together to get another number.
Example: Finding Factor Pairs
Example with 12:
- To find factor pairs of 12, think about which numbers you can multiply together to get 12.
- 1×12=12
- 2×6=12
- 3×4=12
- So, the factor pairs of 12 are:
- (1, 12)
- (2, 6)
- (3, 4)
Visualizing Factor Pairs:
- You can think of factor pairs as making a rectangle with an area of 12 squares. Each pair shows the dimensions of the rectangle.
- 1×12: One row of 12 squares.
- 2×6: Two rows of 6 squares.
- 3×4: Three rows of 4 squares.
Commutativity
Commutativity means that you can swap the numbers you’re adding or multiplying, and the result will be the same. This works for addition and multiplication.
Example: Commutativity of Addition
Example with 3 and 5:
- 3+5=8
- 5+3=8
- It doesn't matter if you add 3 to 5 or 5 to 3; you get the same answer.
Example: Commutativity of Multiplication
Example with 4 and 2:
- 4×2=8
- 2×4=8
- It doesn't matter if you multiply 4 by 2 or 2 by 4; you get the same answer.
Visualizing Commutativity
Addition Example:
Imagine you have 3 red apples and 5 green apples.
- If you count the red apples first: 3 (red) + 5 (green) = 8 (total apples)
- If you count the green apples first: 5 (green) + 3 (red) = 8 (total apples)
- You still have 8 apples either way.
Multiplication Example:
Imagine you have 4 rows of 2 stars each, or 2 rows of 4 stars each.
- 4×2:
* *
* *
* *
* *
= 8 stars
- 2×4:
* * * *
* * * *
= 8 stars
- You still have 8 stars either way.
Summary
- Factor Pairs:
- Two numbers you multiply to get another number.
- Example: Factor pairs of 12 are (1, 12), (2, 6), and (3, 4).
- Commutativity:
- You can swap numbers in addition or multiplication, and the result stays the same.
- Example: 3+5=8 and 5+3=8 (Addition); 4×2=8and 2×4=8 (Multiplication).
By using simple language and visual examples, children can easily grasp these fundamental math concepts.