Least Common Multiple LCM 2 Methods

Product The answer to a multiplication problem. 6 X 6 = 36

What is the product? 7 X 8 = 56

Name the first six multiples of 6 The product of a whole number multiplied times any other whole number. Name the first six multiples of 6 6, 12, 18, 24, 30, 36

Name the first six multiples of 5 5, 10, 15, 20, 25, 30

Common Multiple A Common Multiple is a number that is a multiple of two numbers. Here are common multiples for the numbers 4 and 10 4 = 4, 8, 12, 16, 20, 24 10 = 10, 20, 30, 40, 50,

Least Common Multiple LCM - Smallest number that a set of given numbers divides evenly into. Least Common Multiple - It is useful to know how to do this so you can find a common denominator when adding or subtracting fractions. THERE ARE TWO WAYS TO FIND LCM

Least Common Multiple Method # 1 TO FIND THE LCM OF TWO NUMBERS List the multiples of both numbers Find the least multiple that both numbers have in common.

Least Common Multiple Method # 1 Make a List of Multiples Find the LCM of 10 and 12. 10: 10 , 20 , 30 , 40 , 50 , 60 , 70 , 80 , 90 , 100 ... 12: 12 , 24 , 36 , 48 , 60 LCM = 60

Least Common Multiple Method # 1 Make a List of Multiples Find the LCM of 32 and 40. 32: 32 , 64 , 96 , 128 , 160 , 192 , 224 , 256 ... 40: 40 , 80 , 120 , 160 LCM = 160

What is the Least Common Multiple of 4 & 10 4 = 4, 8, 12, 16, 20, 24 10 = 10, 20, 30, 40, 50,

What is the Least Common Multiple of 6 & 8 6 = 6, 12, 18, 24, 30, 36 8 = 8, 16, 24, 32, 40, 48

What is the Least Common Multiple of 3 & 9 3 = 3, 6, 9, 12, 15, 21, 9 = 9, 18, 27, 36, 45, 54

Method #1 is easy to do! Method #1 is a good method if both of your numbers are really small. What if you have really large numbers? It might take too long to keep listing multiples until you find a common multiple. SO HERE IS METHOD # 2

Least Common Multiple Method # 2 1) Write the prime factorization of each number. Select all common factors ONCE. 3) Then select the remaining factors and multiply.

Least Common Multiple Method # 2 18 20 2 9 2 10 3 3 2 5 Select all common factors once. Then select the remaining factors.

Least Common Multiple Method # 2 45 72 5 9 8 9 3 3 2 4 3 3 2 2 Select all common factors once. Then select the remaining factors.

Least Common Multiple Method # 2 Find the LCM of 48 and 80. 2 48 80 Common Factors Once 2 24 40 2 12 20 2 6 10 3 5 Remaining Factors

SO I GUESS YOU ARE WONDERING Least Common Multiple Method # 2 SO I GUESS YOU ARE WONDERING When Are We Ever Gonna Have To Use This?

Least Common Multiple Method # 2 What is the LCM used for? The LCM is used to find common denominators so that fractions may be easily compared, added, or subtracted.

Least Common Multiple Method # 2 The GCF and LCM are used so regularly that most people find them mentally. GCF = 1 GCF = 5 1) 8 9 2) 15 20 LCM = 72 LCM = 60 copyright©amberpasillas2010

Least Common Multiple Method # 2 The GCF and LCM are used so regularly that most people find them mentally. GCF = 4 GCF = 4 1) 12 20 2) 8 12 LCM = 60 LCM = 24 copyright©amberpasillas2010

Least Common Multiple Method # 2 THE END Take Out Your Study Guide!!!

#9 Multiples A number that is added to itself becomes a multiple. 3, 6, 9, 12, 15, 18 . . . Multiples of 3 = Multiples can go on infinitely forever. The least common multiple (LCM) is the least common number that is a multiple of 2 numbers. It is useful to know this for adding fractions.

LCM is 12 LCM Make a List Method # 1 4 = 4, 8, 12, 16, 20… #10 TO FIND THE LCM OF 4 and 12: 1) List the multiples of both numbers 4 = 4, 8, 12, 16, 20… 12 = 12, 24, 36… 2) Find the least multiple that both numbers have in common. LCM is 12 This method is useful if both numbers are small.

18 20 2 9 2 10 3 3 2 5 #11 LCM Prime Factorization Method # 2 1) List the prime factorization to find the LCM. 18 20 2 9 2 10 3 3 2 5 2) Select all common factors once. 3) Select all remaining factors, and multiply.