Download Least Common Multiple (LCM)

Lesson 1.4 – Least Common Multiple (LCM)
Standard: N.S. 2.4 – Determine the least common multiple and the greatest
common divisor of a whole number; use them to solve
problems with fractions.
Objective: Students will be able to identify the least common multiple
between two numbers.
Vocabulary:
 Multiple – The product of a number and any counting number
 Common multiple – A multiple that is shared by two or more
numbers
 Least Common Multiple (LCM) – The smallest number of
common multiples of two
numbers.
Example 1: Make a list
Find the LCM of 5, 6
Step 1: Make a list of the multiples of each number
Step 2: Stop when you reach a multiple that the two share.
Example 2: Use Prime Factorization to find the LCM
Find the LCM of 75, 60 & 40
Step 1: Find the Prime factorization of each number. Write as
an exponent
Step 2: Circle the greatest power of every prime factor
Step 3: Multiply the circled powers
Whiteboard – CFU
Find the LCM
1.) 12, 18
2.) 3,4
3.) 6, 11, 18
4.) 7, 20, 35
5.) 84, 360
6.) 39, 52,169