GCF = Greatest Common Factor GCF describes itself backwards 1. List the
factors for the numbers EXAMPLE: GCF(16,28) List the factors
of 16: 1,2,4,8,16 The common
factors are 1, 2, and 4 |
LCM = Least Common Multiple LCM also describes itself backwards 1. List the
multiples of the numbers EXAMPLE: LCM(12,18) Multiples
of 12: 12,24,36,48,60,72 and so on The common
multiples are 36, 72, and so on |
The biggest drawback for this method is that the LCM may require a very large list of multiples before the common multiples show up. This method is great for finding the GCF but you may want to also know another method for finding the LCM. |