Transcript factors & multiples - Tapp Middle School

FACTORS
&
MULTIPLES
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ARRANGEMENT OF STARS
Take 6 stars and arrange
them in different
ways
2
1 Row × 6 Stars/Row = 6 Stars
3
3 Rows × 2 Stars per row = 6 stars
4
2 Rows × 3 stars per row = 6 stars
5
6 Rows × 1 Star/Row
= 6 Stars
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As we can see, 6 can be written as
product of two numbers in many
ways:
6=1×6
6=2×3
6=3×2
6=6×1
1, 2, 3 and 6 are exact divisors of 6
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ARRANGEMENT OF SOCCER BALLS
Take 8 soccer balls and arrange
them in different
ways
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Arrangement of 8 in
different ways
1 Row × 8 Balls/Row = 8 Balls
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2 Rows × 4 Balls / Row = 8 Balls
10
4 Rows ×
2 Balls / Row =
8 Balls
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8 Rows × 1 Ball / Row =
8 Balls
12
4 × 5 = 20
Factors
Multiple
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Factors
Factors are the numbers you multiply
together to get a product.
For example, the product 24 has
several factors.
24 = 1 x 24
24 = 2 x 12
24 = 3 x 8
24 = 4 x 6
SO, the factors are 1, 2, 3, 4, 6, 8,
12, 24
Finding Factors
Start with 1 x the number.
Try 2, 3, 4, etc.
When you repeat your factors,
cross out the repeat - you’re done
at this point.
If you get doubles (such as 4 x 4),
then you’re done. Repeats or
doubles let you know you’re done.
What are the factors of 16?
1 x 16
2x8
3 x ??
3 is not a factor, so cross it out
4x4
The factors of 16 are 1,2,4,8,16
doubles = done
What are the factors of 7?
1x7
The only factors of 7 are 1,7
2 x ??
3 x ??
4 x ??
5 x ??
6 x ??
7x1
This works, but it is a repeat. We are done.
4 × 5 = 20
Factors
Multiple
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Multiples
A multiple is formed by multiplying
a given number by the counting
numbers.
The counting numbers are 1, 2, 3,
4, 5, 6, etc.
Example: List the multiples of 4:
4
4
4
4
4
4
x
x
x
x
x
x
1
2
3
4
5
6
=4
=8
=12
=16
=20
=24
Counting Numbers
So, the multiples of 4
are 4, 8, 12, 16, 20, 24,
28, etc.
What are the first five multiples
of 13?
13 x 1 =13
13 x 2 = 26
13 x 3 = 39
13 x 4 = 52
13 x 5 = 65
13, 26, 39, 52, 65
Find the Missing Multiples
24
30
6, 12, 18, ____,
____
___, 6, 9, 12, ____, ____,
21
3
15
18
___, 24, 36, 48, 60, ____
12
72
Prime and Composite Numbers
Prime numbers are
numbers that only
have
two factors: one, and
the
number itself.
EXAMPLES:
3, 5, 7, 11, 31
Composite numbers
have more than two
factors.
EXAMPLES:
6, 18, 30, 100
POINTS TO REMEMBER
• 1 is a factor of every number.
• Every factor of a number is an exact
divisor of that number.
• Every factor is less than or equal to the
given number.
• Number of factors of a given number are
finite.
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POINTS TO REMEMBER
contd
• Every multiple of a number is greater
than or equal to that number.
• The number of multiples of a given
number is infinite.
• Every number is a multiple of itself.
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FACTOR OR MULTIPLE?
For each of numbers in the statements, select
either multiple [M] or factor [F]
 34 × 5 = 170
[F] [M]
 25
[F] [M]
×
[F] [M]
 90
[F] [M]
×
[F] [M]
 45
×
7
[F] [M]
6
[F] [M]
×
= 100
[F] [M]
10 = 900
[F] [M]
[F] [M]

4
[F] [M]
[F] [M]
= 270
[F] [M]
30 = 210
[F] [M]
[F] [M]
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State whether the following
statements are TRUE or FALSE
1. 1 is a factor of every number.
F T
2. The largest factor of any number is the number itself. F
T
3. Number of factors of a given number is infinite. F
T
4.The number of multiples of 5 is 10. F
T
5.The factors of 65 are 1, 5 and 13 only. F T
( Click ‘F’ for false and ‘T’ for true )
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THANK YOU
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CORRECT
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WRONG
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