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multiple
A multiple of a number is
the product of that
number and any other
whole number. Zero is a
multiple of every number.
Multiple
What am I?
Examples:
4: 8, 12, 16, 20, …
7: 14, 21, 28, 35,…
Common multiple
What am I?
A multiple of two or more
numbers.
Common
Multiple
Examples: 3 and 4
0,12, 24, 36, …
Least Common multiple
The smallest nonzero
number that is a multiple
of two or more numbers.
Least
Common
Multiple
What am I?
Examples: 3 and 4
Is 12
Greatest Common Factor
The greatest common factor,
or GCF, is the greatest factor
that divides two numbers.
Greatest
Common
Factor
What am I?
Examples: 6 and 10
6 : 1, 2 , 3, 6
10: 1,2 5,10
Answer: 2
Finding Least Common Multiple of 5 and 6
5:
5, 10 , 15, 20, 25, 30, 35, 40
6:
6, 12, 18, 24, 30, 36, 42
•Simply list the multiples of each number (multiply by 2, 3, 4, etc.)
•Then look for the smallest number that appears in each list.
•30 is the smallest number that is a multiple of both numbers.
Finding Least Common Multiple of 5 and 6
5:
5, 10 , 15, 20, 25, 30, 35, 40
6:
6, 12, 18, 24, 30, 36, 42
•Simply list the multiples of each number (multiply by 2, 3, 4, etc.)
•Then look for the smallest number that appears in each list.
•30 is the smallest number that is a multiple of both numbers.
Independent Practice
6 and 10
6: 12, 18, 24, 30, 36, 42
10: 10, 20, 30, 40
LCM: 30
2 and 9
2: 2,4,6,8,10, 12, 14,16, 18, 20
9: 9,18,27
LCM: 18
6 and 8
6: 6,12,18, 24, 30, 36
8: 8, 16, 24, 32
LCM: 24
3, 5, and 9
3: 3,6,9,12,15,18,21,24,27,30,33,36,39,42,45
5: 10,15,20,25,30,35,40,45,50,55,
9: 9, 18, 27, 36, 45
LCM: 45
Finding the Greatest Common factor of
27 and 54
27:
1,3,9,27
54:
1,2,3,6,9,16,27
•It is sometimes called the Greatest Common Divisor.
•It can be used to simplify (or reduce) fractions.
•Don't let the "greatest" in the name fool you - the GCF is no larger than
the smallest of the numbers.
•The GCF of 27 and 54 is 27.