Least Common Multiple LCM 2 Methods

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

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. LCM = 180 LCM =

Try these Find LCM of 15 and 10 Find LCM of 21 and 14 Find the LCM 60 and 75