FACTORS AND MULTIPLES
Grade 7
KEY TERMS
Factors
Common Factors
Greatest Common
Factor (G.C.F.)
Multiples
Common Multiples
Lowest Common
Multiple (L.C.M.)
Prime
Composite
Sunday, September 16, 2012
Think: Multiplication Facts
Sunday, September 16, 2012
COMMON FACTORS
Factors that are common to two or more numbers are
said to be Common Factors.
For example, 4 = 1 x 4, 2 x 2
6 = 1 x 6, 2 x 3
Therefore, Factors of 4 are 1, 2, and 4
Therefore, Factors of 6 are 1, 2, 3, and 6.
So, the common factors of 4 and 6 are 1and 2.
Greatest Common Factor (G.C.F.) - The largest
common factor two or more numbers have in common.
Therefore, the G.C.F. of 4 and 6 would be 2.
Sunday, September 16, 2012
Sunday, September 16, 2012
PRIME AND COMPOSITE NUMBERS
If a number has only two different factors, 1 and itself,
then the number is said to be a prime number.
For example, 7 = 1 x 7
7 is a prime number since it has only two different factors.
A number that has more than two factors is called a
composite number.
For example, 14 = 1 x 14, 2 x 7
So, 14 is a composite number as it has more than two
factors.
Sunday, September 16, 2012
Think: Skip counting
Sunday, September 16, 2012
COMMON MULTIPLES
Multiples that are common to two or more numbers are
said to be Common Multiples.
E.g., Multiples of 2 are 2, 4, 6, 8, 10, 12, 14, 16, 18, ...
Multiples of 3 are 3, 6, 9, 12, 15, 18, ...
So, common multiples of 2 and 3 are 6, 12, 18, ...
Lowest Common Multiple (L.C.M.) - The
smallest common factor two or more numbers have in
common.
Therefore, the L.C.M. of 2 and 3 would be 6.
Sunday, September 16, 2012