#### Transcript of Multiples, Factors and Primes

Learning Objective:

to be able to define multiples, factors and primes

to be able to find the highest common factor and the lowest common multiple

to be able to express a number as a product of its primes

**Multiples, Factors and Primes**

Success Criteria:

I can tell my friend what a multiple, a factor and a prime numbers is

I can find prime numbers

I can find the highest common factor and lowest common multiple between two or more numbers

I am able to express a number as a product of its primes

**Key Words**

Factor: a number that divides evenly into another number

Prime Number: A number that only has two different factors, one and itself

Multiple: A number that can be divided by another number without a remainder

Prime Factor: A prime number that divides evenly into another number

Highest Common Factor: The biggest same factor between two or more numbers

Lowest Common Multiple: The lowest number that can be evenly divided by two or more numbers

**Prime Numbers**

A number that only has two factors, one and itself

What are some examples of Prime Numbers?

How do you know if a number is Prime?

What is the only even Prime Number? Why?

Highest Common Factor

The biggest same factor between two or more numbers

To find the HCF between two numbers we...

1. List out all the factors for both numbers

2. See which is the biggest same factor in both lists!

Lowest Common Multiple

The smallest same multiple between two or more numbers.

To find the LCM between two numbers we...

1. List out multiples for each number (starting with itself)

2. Stop when we see the first same number

**Prime Factorization**

Each number can be written as a product of its prime factors.

We find Prime Factors in two ways:

1. Factor Trees

2. Division by Primes

Factor Trees

Division by Primes

**Classwork!**

**Classwork!**

Common Factors

1, 2, 3, 4, 6, 8, 12, 24,

24 = the biggest common factor

therefore it is the HCF

ex) Find the HCF between 24 and 48

24: 1, 2, 3, 4, 6, 8, 12, 24

48: 1, 2, 3, 4, 6, 8, 12, 16, 24, 48,

Find the LCM between 3 and 4

3: 3, 6, 9, 12, 15, 18, 21, 24

4: 4, 8, 12, 16, 20, 24

Common Multiples:

12, 24

Smallest multiple = 12

Therefore the LCM between 3 and 4 is 12.

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