NUmber Prop

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NUmber Prop

by yellowho » Sun Feb 20, 2011 5:52 am
What is a quick way to do this:

"What is the smallest possible common multiple of two different integers that are BOTH greater than 250?"
Source: — Problem Solving |

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by Night reader » Sun Feb 20, 2011 6:17 am
a,b --> integers; a>250, b>250
:)
if you are lucky to have on number prime here (do you remember the table of prime numbers beyond 250, yes/no will GMAt test, do you want to solve for >250 still?)
ok let's move on - if two numbers are prime, LCM is simply the product of these numbers; if one is prime and the other is not prime, still multiply both to get LCM;

for all other not prime integers --> perform prime factorization first for a and b; find the highest common factor (HCF) for a and b; multiply a*b and divide by HCF --> a*b/HCF=LCM

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yellowho wrote:What is a quick way to do this:

"What is the smallest possible common multiple of two different integers that are BOTH greater than 250?"