They are elements of the set of numbers of the form 1512*k where k is any integer.
No, 2 and 28 are not multiples of 56, they are factors.
The common multiples of 7, 8, and 8 are the infinite set that includes any multiple of 56. The common multiples are thus 56, 112, 168, 224, 280, and so on.
56
56
Common multiples include any multiple of 7182.
The multiples of 28 include 28, 56 and 84. For them to be common, they need to be compared to another set of multiples.
Multiples of 27 include 27, 54, 81 and so on. For them to be common, they need to be compared to another set of multiples.
1 All the common multiples of 56 and 60 are: 1,2,4
56
56
840
lcm(2, 7) = 14 → first 3 common multiples are: 14, 28, 42; lcm(2, 8) = 8 → first 3 common multiples are: 8, 16, 24; lcm(7, 8) = 56 → first 3 common multiples are: 56, 112, 168; lcm(2, 7, 8) = 56 → first 3 common multiples are: 56, 112, 168.