The first three common multiples are 18, 36, and 54.
The first three multiples of 3 are 3, 6, 9 The first three multiples of 9 are 9, 18, 27 As the lowest common multiples of 3 and 9 is 9, the common multiples of 3 and 9 are the multiples of 9, thus: The first three common multiples of 3 and 9 are 9, 18, 27
First three common multiples of 2 and 6 are 6, 12 and 18.
6, 12, 18
9, 18 and 27
6, 12, 18
3: 3, 6, 9, ... 6: 6, 12, 18, ... 18: 18, 36, 54, ... The lcm(3, 6, 18) = 18, so the multiples of 18 are common multiples of all of them.
18, 36, 54
The first three are 9, 18, and 27.
9 18 27
18, 36, 54
6, 12, 18