How do I find the LCM and HCF of two numbers?

Question

I know the prime factorisation method a little but get confused about when to multiply common vs all factors. Help?

Sonia · Answer

To find the LCM see what is the full form least common multiple so we need to find the least number find the factors and then multiple with the highest powers like for example 12 and 18
12=2x2x3
18=2x3x3
So here for hcf take the common prime factors=2x3=6
For LCM take all the prime factors with highest powers 
Like in 12 two is coming twice and in 18 only once so take two twice and in same case 3 is coming once in 12but in 18 it coming twice so take 3twice and then multiply them like 3x3x2x2=36..if you need I can explain with more examples

How do I find the LCM and HCF of two numbers?

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