Transcript 1.4 Properties of Addition and Multiplication

Commutative and
Associative
Properties of Math
Unit 1-4A
Pages 22-25
Warm Up Problems
1. 17 + 15 = 32
2. 29 + 39 = 68
3. 3(91)=
273
4. 6(15)=
90
Mental Math means doing
math in your head.
There are many
different forms of
properties (or
number solving
orders) that you
can use to quickly
do this.
Definitions
Commutative Property
we can move around and Add or Multiply
numbers in any order we want to.
18 + 9
9 + 18
Think about Communicating, we can talk
with multiple people, any time we want.
https://www.youtube.com/watch?v=O4__F4iX6rc
Definitions
Associative Property
We can group any number together in
pairs to get a equivalent solution.
17+(2+9)
(17+2)+9
Think about 6th Grade Girls. They only
Associate with one girl at a time.
We use these properties to solve
Problems using mental Math.
Simplify
Try to make
groups
of 10’s.
12+4+18+46
12+4+18+42
(12+18)+(4+46)
30 + 50
Now you try!
Simplify
5 x 12 x 2
Try to
make
groups
of 10’s.
Am I:
Associative
Or
Communitive
Now you try!
Simplify
17+5+3+2+15
Try to
make
groups
of 10’s.
Am I:
Associative
Or
Communitive
Now you try!
Simplify
4 x 13 x 5
Try to
make
groups
of 10’s.
Am I:
Associative
Or
Communitive
#1
Simplify
13+9+7+11=
Try to
make
groups
of 10’s.
Am I:
Associative
Or
Communitive
#2
Simplify
19+18+11+32=
Try to
make
groups
of 10’s.
Am I:
Associative
Or
Communitive
#3
Simplify
25 + 7+ 13 + 5=
Try to
make
groups
of 10’s.
Am I:
Associative
Or
Communitive
#4
Simplify
5 x 14 x 4 =
Try to
make
groups
of 10’s.
Am I:
Associative
Or
Communitive
#5
Simplify
4 x 16 x 5 =
Try to
make
groups
of 10’s.
Am I:
Associative
Or
Communitive
#6
Simplify
5 x 17 x 2 =
Try to
make
groups
of 10’s.
Am I:
Associative
Or
Communitive
Distributive
Properties of Math
Unit 1-4 2 of 2
Pages 22-25
Definitions
Distributive Property
When you multiply numbers you can break
them apart to make them easier
4 x 20
3+ 4 x 3
You can remember this property by thinking “When I
DISTRIBUTE something, I give one to everyone in the room.”
6 x 14
6 x (10 + 4)
60 + 24
84
4 x 23
4 x (20 + 3)
80 +12
92
8 x 74
8 x (70 + 4)
560 +32
592
Now You Try It
Use the Distributive Property
to find the Product:
6 x 35
6 x (30 + 5)
180 +30
210
Now You Try It
Use the Distributive Property
to find the Product:
9 x 87
9 x (80 + 7)
720 +63
783
#7
Use the Distributive Property to solve:
Break
apart
and
multiply
by each
place
value.
5 x 24 =
#8
Use the Distributive Property to solve:
Break
apart
and
multiply
by each
place
value.
8 x 52 =
#9
Use the Distributive Property to solve:
Break
apart
and
multiply
by each
place
value.
4 x 39 =
#10
Use the Distributive Property to solve:
Break
apart
and
multiply
by each
place
value.
6 x 14 =
#47
Equal
Determine if each pair of expressions is equivalent:
8 x 35 = (8x30)(8x5)
Yes No
#48
Equal
Determine if each pair of expressions is equivalent:
14+7+6 = 6+14+7
Which Property was used?
Yes No
commutative
1.4 Homework
Page 24 Due: Monday Oct. 24th
15-20
43-46
49 and 50