Multiplying Binomials with FOIL
9-12
2
Finding the Least Common Multiple (LCM)
Lesson Details
Grade Level
6-8
Duration (minutes)
1
Summary
A Grade 6-8 math lesson teaching students how to find the least common multiple (LCM) of two numbers by listing their multiples, identifying the numbers shared by both lists, and selecting the smallest one, using 4 and 6 as the worked example.
Student Worksheet: Finding the Least Common Multiple (LCM)
Teacher Note: Students can watch the video lesson above and answer the questions. Click the “Teacher Answer Key” dropdown below when you are ready to review the solutions!
Key Concepts:
• Multiple: A multiple is what you get when you multiply a number by 1, 2, 3, and so on.
• Common Multiple: A common multiple is a number that appears in the multiples list of two or more numbers.
• Least Common Multiple (LCM): The LCM is the smallest number that appears in both multiples lists.
• Checking Your Answer: You can check an LCM by dividing it by each original number — both should divide evenly with no remainder.
Instructions: Read each question carefully and write your answer in the space provided.
- Question 1: List the first six multiples of 4.
- Question 2: List the first five multiples of 6.
- Question 3: Which numbers appear in both lists? What do we call these numbers?
- Question 4: What is the least common multiple (LCM) of 4 and 6, and how do you know?
- Question 5: Check your answer to Question 4 by dividing it by 4 and by 6. What are the results?
Click to reveal Teacher Answer Key
1. 4, 8, 12, 16, 20, 24
2. 6, 12, 18, 24, 30
3. 12 and 24 appear in both lists. These are called common multiples.
4. The LCM of 4 and 6 is 12, because it is the smallest number that appears in both lists.
5. 12 ÷ 4 = 3 and 12 ÷ 6 = 2. Both divide evenly, confirming 12 is correct.
Disclaimer: This worksheet was generated with AI assistance based on original video content. It is intended for educational reference only. Teachers are encouraged to review and adjust questions to fit their curriculum standards before classroom use.
🎯 Extension Activity: Find the LCM of 5 and 8 by listing multiples of each number until you find the smallest one they share. Check your answer using division.