Download Prime and Composite

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• Find prime
factorization of
each number:
a) 18
b) 75
c) 27
a) 2 x 3 x 3
b) 3 x 5 x 5
c) 3 x 3 x3
Prime and Composite
Number
Definition
Examples
Prime
A whole number that has
two factors: 1 and itself
11, 13, 23
Composite
A number greater than 1
with more than two
factors.
6, 10,8
Neither prime nor
composite
1 has only one factor
0 has an infinite number
of factors
0,1
36
Divisibility Rules
It is divisible by:
Only if:
Examples
2
The ones digit is divisible
by 2
24
3
If the sums of the digits is
divisible by 3
39
5
If the ones digit is 0 or 5
15
9
If the sum of the digits is
divisible by 9
54
10
If the ones digit is 0
20
4÷2=2
24 ÷ 2 = 12
3 + 9 = 12
12 ÷ 3 = 4
15÷ 5 = 3
5+4=9
54 ÷ 9 = 6
20 ÷ 10 = 2
Use the divisibility rules to help find the prime factorization
of composite numbers.
Powers and Exponents (pg. 32)
1.
2.
3.
4.
5.
6.
exponent- how many times the base is used
as a factor
base- the number used as a factor
power- a number expressed using
exponents
squared- to the second power
cubed – to the third power
Exponential form- numbers written with
exponents
exponent
Pg 34-35 prime factorization
using exponents
base
4
2