Factors, Primes & Composite Numbers

Learning Objective: Today factor numbers and determine if they are prime or composite. State objective Teach the meaning it literary works Literary works refers to literature Have students repeat literature

What will we learn today? Today we will factor numbers and determine if they are prime or composite. Have students share with partners the objective then call on 3 non volunteer to share today’s objective

What is the answer to a multiplication problem called? Partner Share What is 3 x 7? What is the answer to a multiplication problem called?

Definition Product Product – An answer to a multiplication problem. 7 x 8 = 56 Product

Definition Factor – a number that is multiplied by another to give a product. 7 x 8 = 56 Factors

What are the factors? (What two numbers make that product?) 6 x 7 = 42 6 & 7 7 x 9 = 63 7 & 9 8 x 6 = 48 8 & 6 4 & 9 4 x 9 = 36

7 Definition 7 is prime because the only numbers Prime Number – a number that has only two factors, itself and 1. 7 7 is prime because the only numbers that will divide into it evenly are 1 and 7.

Examples of Prime Numbers 2, 3, 5, 7, 11, 13, 17, 19 Special Note: One is not a prime number.

The factors of 8 are 1, 2, 4, 8 because 1x8=8 and 2x4=8 Definition Composite number – a number that has more than two factors. 8 The factors of 8 are 1, 2, 4, 8 because 1x8=8 and 2x4=8

Examples of Composite Numbers 4, 6, 8, 9, 10, 12, 14, 15 Special Note: Every whole number from 2 on is either composite or prime.

Our Lonely 1 One is not a prime nor a composite number. It is not prime because it does not have exactly two different factors. It is not composite because it does not have more than 2 factors. Special Note: One is not a prime nor a composite number.

Why is it important to understand?

How to use a factor tree Step 1 – Write down two factors. 48 Step 1 – Write down two factors. (What two numbers make 48?) 48 6 8 48

How to use a factor tree Step 2 – Find factors of these numbers until all factors are prime. (what makes a 6? What makes an 8?) 48 6 2 3 8 4 48 6 2 3 8 48 6 8 48

How to use a factor tree Step 2 – Find factors of these numbers until all factors are prime numbers. 48 6 2 3 8 4 48 6 2 3 8 4

Composite How to use a Factor Tree Factors of 48 are: 1,2,3,4,6,8,48 Step 3 – Write the numbers from least to greatest. Determine if the number is prime or composite. 48 6 2 3 8 4 Factors of 48 are: 1,2,3,4,6,8,48 Hint: only write each digit once. Composite

Composite Factors of 6 are: Factor this number 1,2,4,6 Step 1 – Write down two factors. Step 2 – Find factors of these numbers until all factors are prime Step 3 – Write the numbers from least to greatest. Determine if the number is prime or composite. Factor this number Composite 6 2 3 Factors of 6 are: Hint: only write each digit once. 6 1,2,4,6

Composite Factors of 8 are: Factor this number 1,2,4,8 8 Step 1 – Write down two factors. Step 2 – Find factors of these numbers until all factors are prime Step 3 – Write the numbers from least to greatest. Determine if the number is prime or composite. Factor this number 8 2 4 Composite 8 2 4 Factors of 8 are: Hint: only write each digit once. 8 1,2,4,8

Composite Factors of 6 are: Factor this number 1,2,5,10 Hint: only write each digit once. 10 1,2,5,10

Composite Factors of 8 are: Factor this number 1,2,4,5,20 20 Hint: only write each digit once. 20 1,2,4,5,20

Prime Factors of 7 are: 1,7 Factor this number Hint: only write each digit once.

Prime Factors of 13 are: 1,13 Factor this number Hint: only write each digit once. 13

Now you try! Factor this number What did we learn to factor today? Why is it important? Now you try! Factor this number Prime or composite? Factors of ___ are: _____________ Hint: only write each digit once. Don’t forget 1 and itself! 25

Now you try! Factor this number Prime or composite? Factors of ___ are: _____________ Hint: only write each digit once. Don’t forget 1 and itself! 24

Now you try! Factor this number Prime or composite? Factors of ___ are: _____________ Hint: only write each digit once. Don’t forget 1 and itself! 17

Factor this number Prime or composite? Factors of __________ are: Step 1 – Write down two factors. Step 2 – Find factors of these numbers until all factors are prime Step 3 – Write the numbers from least to greatest. Determine if the number is prime or composite. Prime or composite? Factors of __________ are: Hint: only write each digit once. Don’t forget 1 and itself! Factor this number Print this slide for use in whiteboards