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Lesson 4: Week 4

HCF visualized

Finding the HCF from prime factors can sometimes be hard to imagine. Let's look at an interesting way to visualise finding the HCF of two numbers using prime factorisation. Created by. Created by Aanand Srinivas.

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• What is main purpose of HCF?
• HCF is useful in cases when you want different amounts of things to be arranged in the same number of order.

For example there are 32 soldiers and 48 bandsman and during the parade you want them to march in the same number of rows. So , you calculate the HCF which is 8 and thus you can make 8 rows each for each group.
• I understand H.C.F BUT, i'm not understanding how you are doing it
• what is the difference HCF and GCF?
• They are the same. HCF is the Highest Common Factor, GCF is the Greatest Common Factor. Greatest means Highest. :) Upvote it please..
• Can you also do this process using the ladder without making this so complicated and soo long?! Because its kinda confusing me? :(
• According to me, if you want to find the HCF, their are many ways. The ladder one is one way of doing it. In that, we must take the two numbers who's HCF we want, beside each other. Then, we find prime numbers that are divisible by both the numbers and then divide the numbers. We carry on this process until we reach 1 by continuously dividing both the numbers. Then we multiply all the prime numbers on the left to get the HCF. If this process is kinda difficult, I'd recommend you to watch and try the Euclid's division algorithm to find HCF - https://youtu.be/H1AE2Se8A5E I found it simple and easy. Hopes that you will too.
(1 vote)
• it is the
Factor tree methord
(1 vote)
• that wasent a question