1 / 13

Least Common Multiple

Least Common Multiple . Algebra Seminar 2012-2013. What is LCM?. LCM stands for L east C ommon M ultiple LCM is used to find a common denominator for two fractions in order to compare them. LCM is defined as: the smallest number that both numbers are factors of.

tallulah-lynch
Download Presentation

Least Common Multiple

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. Least Common Multiple Algebra Seminar 2012-2013

  2. What is LCM? • LCM stands for Least Common Multiple • LCM is used to find a common denominator for two fractions in order to compare them. • LCM is defined as: the smallest number that both numbers are factors of. • Lets watch a short video from www.unitedstreaming.com on LCM.

  3. Finding the LCM Least Common Multiple (LCM): Method 1: Make a list of multiples Ex: Find the LCM of 4 and 9 9: 9, 18, 27, 36, 45, 4: 4, 8, 12, 16, 20, 24, 28, 32, 36, 40 44 36 is the LCM of 4 and 9

  4. More Examples of LCM Ex: Find the LCM of 10 and 12 10, 20, 30, 40, 50, 60, 70, 80, 90, 100 10: 12: 12, 24, 36, 48, 60, 72, 84, 96, 108 60 is the LCM of 10 and 12 Ex: Find the LCM of 6 and 8 6, 12, 18, 24, 30, 36, 42, 48, 54, 60, 66, 72 6: 8: 8, 16, 24, 32, 40, 48, 56, 64, 72, 80, 88 24 is the LCM of 6 and 8

  5. Tips for finding the Least Common Multiple 1. Make a list of multiples for each number 2. Look for the smallest number they have in common 3. If you are looking for the LCM of more than two numbers make more lists. The LCM must be common to ALL of the numbers. 5 = 5, 10, 15, 20, 25, 30, 35 6 = 6, 12, 18, 24, 30, 36 10 = 10, 20 , 30, 40, 50 , 60

  6. Using the LCM to Put Fractions in Order Put the following fractions in order from greatest to least without using a calculator: Without a calculator, we cannot change the fractions to decimals. We will have to use LCM.

  7. Using the LCM to Put Fractions in Order Step 1: Find the LCM of the denominators

  8. The LCM of 6, 12, 9, and 3 is…. 6: 6, 12, 18, 24, 30, 36, 42, 48… 12: 12, 24, 36, 48 … 9: 9, 18, 27, 36, 45 … 3: 3, 6, 9, 12, 15, 18, 21, 24, 27 30, 33, 36, 39, 42 … LCM = 36

  9. Step 2: Write equivalent fractions. x 6 6 21 x 3 36 36 x 6 x 3 x 4 20 24 x 12 36 36 x 4 x 12

  10. Step 3: Compare the numerators Greatest to Least 21 6 36 36 24 20 36 36

  11. Put the Fractions in Order Now try this one.

  12. The correct answer is: Here are some more to try.

More Related