Can someone please show me how to find the lcm useing prime factorization ? i am so confused about this here is a sample problem 18 and 24

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- Apr 25th 2006, 10:04 PMSandra14factorization ?
Can someone please show me how to find the lcm useing prime factorization ? i am so confused about this here is a sample problem 18 and 24

- Apr 26th 2006, 05:10 AMearbothQuote:

Originally Posted by**Sandra14**

1. Transform both numbers into a product of prime factors:

18 = 2 * 3 * 3

24 = 2 * 2 * 2 * 3

2. The lcm consists of all prime factors so that each number is completely in the lcm:

$\displaystyle lcm = \underbrace{2 * 3 * 3}_{\csub{thats\ for\ 18}}* \underbrace{2*2}_{\csub{addition\ to\ get\ 24}}=72$

Greetings

EB - Apr 26th 2006, 10:08 AMearbothQuote:

Originally Posted by**Sandra14**

it's me again.

I've attached a diagram to show you how you can find the lcm for 2**and more**numbers by using prime factorization.

Maybe you need some time to understand the "mechanic" which is used. But if you've understand it, it's a very easy way to do a very unpleasent calculation.

Good luck.

EB - Apr 26th 2006, 01:21 PMThePerfectHackerQuote:

Originally Posted by**Sandra14**

$\displaystyle \gcd(a,b)\cdot \mbox{lcm} (a,b)=ab$

If you understand what I said, good. If you like me to explain how to use this to find both the greatest common divisor and lowest common multiple please ask.