What is the LCM and the GCF of 195 and 390?

Answer 1

To find the LCM and gcf of the numbers write them in prime factorisation in power form. Then for the LCM take the highest power of every prime across the numbers, for the gcf take the lower power of every common prime, and multiply them together:

195 = 3 x 5 x 13

390 = 2 x 3 x 5 x 13

LCM = 2 x 3 x 5 x 13 = 390

gcf = 3 x 5 x 13 = 195

but since 195 x 2 = 390

LCM is 390

gcf is 195

easy peasy.