Transcript 4.2, 4.4 Least Common Multiple and Greatest Common Factor

4.2, 4.4 Least Common Multiple
and Greatest Common Factor
Least Common Multiple
LCM is…
LEAST: Smallest
COMMON: Shared
MULTIPLE: Product of that # and
another whole #
Least Common Multiple
Find the LCM of 12 and 15.
12 - 12, 24, 36, 48, 60, 72, 84, 96, 108
15 - 15, 30, 45, 60, 75, 90, 105
60 is the LCM of 12 and 15.
Greatest Common Factor
GCF is…
GREATEST: Largest
COMMON: Shared
FACTOR: One of two or more expressions
that are multiplied together to get a product.
Greatest Common Factor
Find the GCF of 24 and 28.
24 - 1, 2, 3, 4, 6, 8, 12, 24
28 - 1, 2, 4, 7, 14, 28
4 is the GCF of 24 and 28.
The Ladder Method
Find the GCF and LCM of the following numbers.
3
12
15
4
5
GCF: 3
LCM: 3 • 4 • 5
60
The Ladder Method
Find the GCF and LCM of the following numbers.
2
20
6
10
3
GCF: 2
LCM: 2 • 10 • 3
60
The Ladder Method
Find the GCF and LCM of the following numbers.
2
8
12
2
4
6
GCF: 2 • 2
4
3
LCM: 2 • 2 • 2 • 3
24
2
The Ladder Method
Find the GCF and LCM of the following numbers.
2
14
7
7
1
42
21
GCF: 2 • 7
14
3
LCM: 2 • 7 • 1 • 3
42
The Ladder Method
Find the GCF and LCM of the following numbers.
3
15a3
18a
a
5a3
6a
5a2
6
GCF: 3 • a
3a
LCM: 3 • a • 5a2 • 6
90a3
The Ladder Method
Find the GCF and LCM of the following numbers.
3
3x
9x2
x
x
3x2
GCF: 3 • x
3x
3x
LCM: 3 • x • 1 • 3x
9x2
1
The Ladder Method
Find the GCF and LCM of the following numbers.
8
16b4 24b2
b2
2b4
2b2
3b2
3
GCF: 8 • b2
8b2
LCM: 8 • b2 • 2b2 • 3
48b4
The Ladder Method
Find the GCF and LCM of the following numbers.
5
25x2y3 30x4y2
x2
5x2y3
y2
6x4y2
5y3
6x2y2
5y
6x2
GCF: 5 • x2 • y2
5x2y2
LCM:5•x2•y2•5y•6x2
150x4y2