### Possible Answer

To find both of these you first need to break up the numbers into their prime factors: 18 = 2x3x3 20 = 2x2x5 Th next step is to identify any common prime factors. The only common prime factor between these two is a single 2. The GCF is therefore 2. The LCM is every other factor multiplied ... - read more

Greatest common factor means the factor that goes (for example) 18 and 20, but the biggest. Improve answer. ... What is the gcf and LCM of 18 and 20?: 3x3x2x2x5=180, so the LCM of 18 and 20 is 180. What is the GCF of 12 18 and 20? - read more

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