Question: what is the LCM of 210 and 54 and the LCM of 42 and 126

Hi Alex,

I am going to do a similar problem.

Find the LCM of 231 and 294

First I would find the prime factorization of the two numbers

231 = 3 7 11
294 = 2 3 7²

If N is a multiple of 231 then the prime factorization of N must contain at least one 3, one 7 and one 11. If N is also a multiple of 294 then the prime factorization of N must contain at least one 2, at least one 3 and at least two 7's. Thus the smallest such N is

N = 2 3 7² 11

This is the LCM of 231 and 294.

Penny