Hi there -
I'm feeling pretty good about my GMAT quants (test consistently between Q47 and Q49) ... But I want to close the gap because my verbal sucks.
I'm getting killed on prime factorizations - can anyone point me to any good online or offline references?
What is exactly your biggest problem with it ? can you post some questions ?
GCF - Greatest Common Factor
Largest possible common factor between numbers
LCM - Lowest Common Multiple
Largest possible common multiple between numbers
To find the GCF/LCM, you will need to do prime-factorization. This means reducing a number to its prime-factor form.
GCF/LCM of 4,18
4 = 2*2
To find the GCF, take the multiplication of the common factors (pick the lowest power of the common factors) In this case, GCF = 2.
To find the LCM, take the multiplication of all the factors (pick the higest power of the common factors). In this case, LCM=2*2*3*3=36