There are an infinite number of common multiples for 7 and nine. Some of them are 63, 126, 189, 252, 315, and 378.
63
The common multiples of an set of numbers are the multiples of their lowest common multiple. lcm(7, 8, 9) = 504 → the first 3 common multiples of 7, 8, 9 are 504, 1008, 1512.
The lowest common multiple of 7 and 9 is 63. The common multiples of 7 and 9 are therefore the infinite set of multiples of 63. Thus, the common multiples of 7 and 9 are 63, 126, 189, 252, 315, 378, 441, 504, 567, 630, 693, and so on.
504 is the least common multiple of 7, 8 and 9. All numbers that are multiples of 504 are multiples of 7, 8 and 9 as well
Common multiples of 7 and 4 include any multiple of 28.
315
63, 126, 189 and so on.
Any multiple of 252
They are 63 and 126
63
Common multiples of 9 and 10 are all of the multiples of 90.
63, 126, 189.
Multiples of 3 are 3, 6, 9 and so on. Multiples of 7 are 7, 14, 21 and so on. The common multiples of 3 and 7 include 21, 42, 63 and so on.