20 pinkgal333:20, 40, 60 are all common multiples.
Any multiple of 20.
4, 6 and 10
5
Any multiple of 20.
20, 40, 60
8/10/12
10, 20, 30 The common multiples of 5 and 10 are multiples of their lowest common multiple. The lcm of 5 and 10, is 10. Thus the first three common multiples are 10, 20, 30.
The Lowest Common Multiple (LCM) of 3 and 10 would be 30
20, 40, 60 are all common multiples.
The first 5 common multiples are the first 5 multiples of their lowest common multiple (LCM) LCM(9, 10) = 90 → first 5 common multiples are 90, 180, 270, 360, 450.
Multiples of 5 and 10 are called common multiples.