1. Factors and Primes

2. Definition Product Product – the answer to a multiplication problem.
5 x 6 = 30
Product

3. Definition
Factor – a number that divides evenly into another.
30 ÷ 6 = 5
Factor

4. What are the factors?
6 x 7 = 42
6 & 7
7 x 9 = 63
7 & 9
8 x 6 = 48
8 & 6
4 & 9
4 x 9 = 36

5. 5 Definition 5 is prime because the only numbers
Prime Number – a number that has only two factors, itself and 1. 5
5 is prime because the only numbers
that will divide into it evenly are 1 and 5.

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

7. Definition
Prime Factorization – A way to write a number as the product of prime factors.
2 x 2 x 3 = 12 or 2
2 x 3 = 12

8. How to Do Prime Factorization Using a Factor Tree
Step 1 – Start with a number. 48
Step 2 – Write down a pair of
factors that make this number.
6 x 8 = 48

9. How to Do Prime Factorization Using a Factor Tree
Step 3 – Find factors of these factors.
6 x 8 = 48
2 x 3 x 2 x 4 = 48

10. How to Do Prime Factorization Using a Factor Tree
Step 4 – Find factors of these numbers
until all factors are prime numbers.
6 x 8 = 48
2 x 3 x 2 x 4 = 48
2 x 3 x 2 x 2 x 2 = 48

11. How to Do Prime Factorization Using a Factor Tree
Step 5 – Count how many numbers are
the same and write them in index form.
6 x 8 = 48
2 x 3 x 2 x 2 x 2 = 48
2 x 2 x 2 x 2 x 3 = 48 4
2 x 3 = 48

12. Prime factor this number4
2 x 2
= 4 2
2 = 4

13. Prime factor this number6
2 x 3
= 6

14. Prime factor this number8
2 x 4
= 8
2 x 2 x 2 = 8 3
2 = 8

15. Prime factor this number9
3 x 3
= 9 2
3 = 9

16. Prime factor this number10
2 x 5
= 10

17. Prime factor this number12
3 x 4
= 12
3 x 2 x 2 = 12
2 x 2 x 3 = 12 2
2 x 3 = 12

18. Prime factor this number14
2 x 7
= 14

19. Prime factor this number15
3 x 5
= 15

20. Prime factor this number16
4 x 4
= 16
2 x 2 x 2 x 2 = 16 4
2 = 16

21. Prime factor this number18
3 x 6
= 18
3 x 2 x 3 = 18
2 x 3 x 3 = 18
2 x 3 = 18 2

22. Prime factor this number20
4 x 5
= 20
2 x 2 x 5 = 20
2 x 5 = 20 2