84, 168, 252 and so on.
1 and 2 are common factors. 84 and 168 are common multiples.
2,2,7,2
If that's 9, 14 and 21, the first three common multiples are 126, 252 and 378.
The Least Common Multiple (LCM) for 10 12 14 is 420.
14, 28, 42.
14, 28, 42.
420 is the LCM
Any multiple of 84
The lowest common multiple is 84
14, 28 and 42
14, 28, 42
Any multiple of 420.