How to find the Highest Common Factor

*** WHAT'S COVERED ***
1. Defining the Highest Common Factor (HCF).
2. Finding the HCF by listing factors of two numbers.
3. Finding the HCF using prime factorisation.
* Identifying common prime factors from the lists.
* How to handle prime factors that appear multiple times.

*** EXAM BOARD INFO ***
Suitable for courses across the world.
In the UK:
KS3 - Only need to know the first method (up to 1:55)
GCSE Foundation - Only need to know the first method (up to 1:55)
GCSE Higher - All suitable

*** CHAPTERS ***
0:00 Introduction to Highest Common Factor (HCF)
0:26 Method 1: Listing Factors
1:09 Listing Factors Practice: 12 and 18
1:56 Method 2: Using Prime Factors
2:40 Prime Factors - Handling Repeated Factors
3:15 Prime Factors Practice: 28 and 42
3:57 Prime Factors Practice: 132 and 420

*** PLAYLISTS ***

#GCSE #KS3 #Maths #study #revision #school #exam #AQA #OCR #Edexcel #IGCSE #IB #AP

[Cognitoedu]

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- A huge number of fully-hinted questions that take you step-by-step through some of the trickiest calculations & concepts.
- A comprehensive bank of past exam papers, organised both by year, and also by topic.

Amadeus & Tom

[UrCrushLaughed]

It's been 4 years since this video was uploaded and is still helping people like me, thanks a lot cognito for making such a nice and brief video.

[Neon_JohnYT]

I like the way these videos can teach me how to do whatever it is in 20 seconds but my maths book cant teach me it in 20 minutes. Thanks for 139 likes MuM IM FaMouS

[TanatswaAshleyChinyama]

Bro summarises one maths lesson in within 10 minutes, Bro is the goat

[bulelwangxiki]

If I pass my test with more than 70 %, you will have changed my life coz I am a 40%student in math so thanks I am getting the concept so far love you Cognito

[Katie_]

I love how your videos have the words in different colors to show the different parts, like in your lcm video where u showed a common factor and the lcm and the words were different colors in the lcm part to show it’s difference, it’s really cool for me to see!

[alpharano]

what the, you make everything so easy i learnt it in two mins instead of an hour if i were to learn it in school, your a heroe

[randomvidz]

Wow I went throught many maths teachers on YouTube and you explain it the best

[Madmark]

I think I spotted an error in your video, @4:25 "find the HCF of 132 and 420" you then have "the prime numbers of 28 and 42" instead 132 and 420. The prime numbers listed are that of 132 and 420.

[univerxse]

I am actually Asian but I have a math subject, sometimes it confuse me but now I know because of this video! Thank You so much :)

[bakhtawarnawaal]

I am very weak in maths but you solved my problems.

[froggyfrog]

I believe there is a mistake in this video. On the last sum it says find the HCF of 132 & 420, then if gives the prime factors but says of 28 & 42 again.

[akhileshsridharabirami]

I know what HCF is but I needed a method to find the HCF. You have made it so easy to find HCF now Thank You very Much😊

[koktaoyong]

Thank You so much, this made a lot of sense, I hope I can past my exam.

[Nkouraa]

I have a huge exam tomorrow and your videos really help me understand the factors and multiples but in primary school they couldn't teach ME ANYTHING, so thanks

[mahveensharjeel]

i have been searching a good and nice video to explain me HCF but i couldnt understand until i watched this!!thank youuu

[temmymol]

BRO I COULD UNDERSTAND THIS BY WATCHING NUMBERBLOCK

[kawaiiaza]

Thanks! I am learning this in grade 9 but I forgot how to do it this was really helpful

[zoee._.]

coming back in high school because it became irrelevant the past few years but we need it now.. gives me back fifth grade memories, thank you for making it simple enough :')

[aisha]

thank you so much, i never learnt this method, it's much easier to understand!!