455
1,7
42
56
It is: 42
42 is the LCM of 3, 6 and 7. All multiples of 42 are multiples of 3, 6 and 7
35 7x5
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 LCM is: 21
The LCM is: 168
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.
You need at least two numbers to find an LCM.
There are infinitely many common multiples of 3, 5 and 7, each one 105 larger than the previous one. Or to put it another way: the common multiples of 3, 5 and 7 are the multiples of their lowest common multiple which is 105. ie their common multiples are all the multiples of 105, of which there is no end - there is an infinite number of multiples of 105 (or any other number [except zero]).