Download presentation

Presentation is loading. Please wait.

Published byUrsula Black Modified about 1 year ago

1
Today we will determine the prime factors of all the numbers through 50 Prime Number – a number that has only two factors, itself and 1. Factor – a number that divides evenly into another. Composite number – a that has more than two factors.

2
Definition Product – An answer to a multiplication problem. 7 x 8 = 56 Product

3
Definition Factor – a number that is multiplied by another to give a product. 7 x 8 = 56 Factors

4
Definition Factor – a number that divides evenly into another. 56 ÷ 8 = 7 Factor

5
Remember you learned factors in 4 th grade? 6 x 7 = 42 6 & 7 What are the factors of 42?

6
What are the factors? 42 ÷ 7 = 6 63 ÷ 9 = 7 7 & 6 9 & 7

7
Definition 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.

8
Examples of Prime Numbers 2, 3, 5, 7, 11, 13, 17, 19 Special Note: One is not a prime number.

9
Definition Composite number – a that has more than two factors. 8 The factors of 8 are 1, 2, 4, 8

10
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.

11
Our Lonely 1 Special Note: 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.

12
Definition Prime Factorization – A way to write a composite number as the product of prime factors. 2 x 2 x 3 = 12 So the prime numbers are 2 and 3

13
Why is it important to know about Prime Factorization? It will be in the CST. It helps you understand multiplication and division better. A prime number can only be divided by 1 or itself, so it cannot be factored any further! Every other whole number can be broken down into prime number factors. It is like the Prime Numbers are the basic building blocks of all numbers. What are other reasons to know the all the prime factors to 50?

14
Let’s “draw” some Prime factor trees! 12 Steps! 1.Write down the composite number. 2.Choose factors that equal the composite number (not the number times 1) 3.Keep breaking the number down until all you have are prime numbers! 4.Remember to circle your prime numbers! 5.Write down your prime numbers from smallest to greatest! 2 x 6 Prime! 2 x 3 x 2 2, 2, & 3

15
Let’s “draw” some Prime factor trees! 16 Steps! 1.Write down the composite number. 2.Choose factors that equal the composite number (not the number times 1) 3.Keep breaking the number down until all you have are prime numbers! 4.Remember to circle your prime numbers! 5.Write down your prime numbers from smallest to greatest! 4 x 4 2 x 2 x 2 x 2 2, 2, 2, & 2

16
Let’s “draw” some Prime factor trees! 25 Steps! 1.Write down the composite number. 2.Choose factors that equal the composite number (not the number times 1) 3.Keep breaking the number down until all you have are prime numbers! 4.Remember to circle your prime numbers! 5.Write down your prime numbers from smallest to greatest! 5 x 5 5 & 5

17
Let’s review what we learned! What are composite numbers? numbers that have more than two factors. What are prime numbers? a number that has only two factors, itself and 1. What is the prime factorization of 20?

Similar presentations

© 2017 SlidePlayer.com Inc.

All rights reserved.

Ads by Google