# Finding the LCM

In this lesson, we will find the 'Lowest Common Multiple' of two integers using a Venn diagram to compare their prime factors.

#### Unit quizzes are being retired in August 2023

Why we're removing unit quizzes from the website >
Quiz:

# Intro quiz - Recap from previous lesson

Before we start this lesson, let’s see what you can remember from this topic. Here’s a quick quiz!

Q1.18 is a multiple of 6?

1/4

Q2.Find the HCF and the LCM of 6 and 15.

2/4

Q3.You can find the LCM of any 2 numbers by multiplying them together!

3/4

Q4.A green light flashes every 15 minutes and a red light flashes every 50 minutes. If they start to flash at the same time, after how long will they both flash together?

4/4

#### Unit quizzes are being retired in August 2023

Why we're removing unit quizzes from the website >
Quiz:

# Intro quiz - Recap from previous lesson

Before we start this lesson, let’s see what you can remember from this topic. Here’s a quick quiz!

Q1.18 is a multiple of 6?

1/4

Q2.Find the HCF and the LCM of 6 and 15.

2/4

Q3.You can find the LCM of any 2 numbers by multiplying them together!

3/4

Q4.A green light flashes every 15 minutes and a red light flashes every 50 minutes. If they start to flash at the same time, after how long will they both flash together?

4/4

# Video

Click on the play button to start the video. If your teacher asks you to pause the video and look at the worksheet you should:

• Click "Close Video"
• Click "Next" to view the activity

Your video will re-appear on the next page, and will stay paused in the right place.

# Worksheet

These slides will take you through some tasks for the lesson. If you need to re-play the video, click the ‘Resume Video’ icon. If you are asked to add answers to the slides, first download or print out the worksheet. Once you have finished all the tasks, click ‘Next’ below.

#### Unit quizzes are being retired in August 2023

Why we're removing unit quizzes from the website >
Quiz:

# Finding the LCM

Don’t worry if you get a question wrong! Forgetting is an important step in learning. We will recap next lesson.

Q1.

1/4

Q2.The Venn diagram shows the product of primes for numbers A and B. What is the value of B?

2/4

Q3.The Venn diagram shows the product of primes for numbers A and B. What is the LCM of these two numbers?

3/4

Q4.Find the LCM of 38 and 42.

4/4

#### Unit quizzes are being retired in August 2023

Why we're removing unit quizzes from the website >
Quiz:

# Finding the LCM

Don’t worry if you get a question wrong! Forgetting is an important step in learning. We will recap next lesson.

Q1.

1/4

Q2.The Venn diagram shows the product of primes for numbers A and B. What is the value of B?

2/4

Q3.The Venn diagram shows the product of primes for numbers A and B. What is the LCM of these two numbers?

3/4

Q4.Find the LCM of 38 and 42.

4/4

# Lesson summary: Finding the LCM

## Time to move!

Did you know that exercise helps your concentration and ability to learn?

For 5 mins...

Move around:
Walk

On the spot:
Dance