1 / 18

Prime Factorization

Prime Factorization. Used to find the LCM and GCF to help us add and subtract fractions. Factors. A factor is a number that divides another number with no remainder. Examples: factors of 12 are 1 & 12, 2 & 6, 3 & 4. Prime numbers. A number that has only two factors, 1 and itself.

stuart-maldonado
Download Presentation

Prime Factorization

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Prime Factorization Used to find the LCM and GCF to help us add and subtract fractions.

  2. Factors • A factor is a number that divides another number with no remainder. • Examples: factors of 12 are 1 & 12, 2 & 6, 3 & 4

  3. Prime numbers • A number that has only two factors, 1 and itself. • Examples: 2, 3, 5, 7, 11, 13, 17…

  4. Prime Factorization • The prime factorization of a number is the product of its prime factors. • Example: of 12- or

  5. Factor Trees • Use a factor tree to break down a number to get to the prime numbers (till you can’t break it down anymore) or

  6. Another example

  7. One more example…

  8. Now you try … • Find the prime factorization of: • 40 • 48

  9. GCF The Greatest Common Factor between at least two numbers… used to simplify fractions.

  10. GCF • The greatest common factor of two or more numbers is the greatest factor that is in common to those numbers. • The GCF can be found by: • Listing all the factors of each number and then finding the largest number in all lists to give the GCF. • Do a factor tree of each number and the prime factors that are in all trees multiply to give the GCF.

  11. Listing all the factors… • This works best when the numbers are small and have few factors. • 12 and 15 • Factors of 12: 1, 2, 3, 4, 6, 12 • Factors of 15: 1, 3, 5, 15 • GCF= 3

  12. Do a factor tree… • This works best when the numbers are large and have many factors. These two trees share a 3 and 5. Multiply these two together and get 15. GCF=15

  13. Try another with a factor tree • 45 and 81 • GCF=3x3=9

  14. Now you try… Find the GCF • 16 and 24 • 12, 48, 72

  15. LCM Least Common Multiple between at least two numbers… used to find a common denominator to help add and subtract fractions.

  16. Multiple • The multiple of a number is a product of that number and a whole number… • Meaning multiply! • Multiples of 5: • 5, 10, 15, 20, 25, 30… • Multiples of 3: • 3, 6, 9, 12, 15, 18, 21…

  17. LCM • Least Common Multiple is the smallest multiple of two or more numbers. • The easiest way to find the LCM: • Start to list all the multiples of the numbers involved and stop as soon as you have a number in common to both lists. • Ex: between 3 and 5 • 5, 10, 15, 20… • 3, 6, 9, 12, 15… • So the LCM is 15!

  18. You try it! • Find the LCM between 4 and 9 • Make a list of multiples of each number. • 4, 8, 12, 16, 20, 24, 28, 32, 36, 40 • 9, 18, 27, 36.. • LCM = 36!

More Related