# Finding the HCF

In this lesson, we will find the 'Highest Common Factor' of two integers by comparing their prime factors using a Venn diagram.

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.

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

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.

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

# 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.

Quiz:

# Finding the HCF

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

Q1.Find 28 as the product of its prime factors.

1/4

Q2.True or False, Number A and B are 28 and 42?

2/4

Q3.What is the HCF of 28 and 42?

3/4

Q4.What is the HCF of 48 and 72?

4/4

Quiz:

# Finding the HCF

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

Q1.Find 28 as the product of its prime factors.

1/4

Q2.True or False, Number A and B are 28 and 42?

2/4

Q3.What is the HCF of 28 and 42?

3/4

Q4.What is the HCF of 48 and 72?

4/4

# Lesson summary: Finding the HCF

## Time to move!

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

For 5 mins...

Move around:
Climb stairs

On the spot:
Chair yoga