The common multiples of 120 and 30 are:
120, 240, 360, 480, 600, 720, 840, 960, 1080, 1200, 1320, 1440, 1560, 1680, 1800, 1920, 2040, 2160, 2280, 2400, 2520, 2640, 2760, 2880, 3000, 3120, 3240, 3360, 3480, 3600, 3720, 3840, 3960, 4080, 4200, 4320, 4440, 4560, 4680, 4800, 4920, 5040, 5160, 5280, 5400, 5520, 5640, 5760, 5880, 6000, 6120, 6240, 6360, 6480, 6600, 6720, 6840, 6960, 7080, 7200, 7320, 7440, 7560, 7680, 7800, 7920, 8040, 8160, 8280, 8400, 8520, 8640, 8760, 8880, 9000, 9120, 9240, 9360, 9480, 9600, 9720, 9840, 9960, 10080, 10200, 10320, 10440, 10560, 10680, 10800, 10920, 11040, 11160, 11280, 11400, 11520, 11640, 11760, 11880, 12000, ...
The multiples of 20 are 20, 40, 60, 80, 100, 120... The multiples of 30 are 30, 60, 90, 120, 150... The multiples of 15 are 15, 30, 45, 60, 75, 90, 105, 120, 135... The common multiples of 20, 30, and 15 are 60, 120, 180, 240...
It is 120
Multiples of 30 from 120 to 990
Any multiple of 120.
60, 120, 180 and so on.
60 and 120
60, 120, 180 and so on.
60 and 120
The common multiples of 5 and 6 are the multiples of their lowest common multiple (which is 30), so there are infinitely many common multiples of 5 and 6. The first five are: 30, 60, 90, 120, 150.
30, 60, 90, 120, 150, 180 . . .
The common multiples of 6 and 5 are 30, 60, 90, 120, 150, 180, and so on.
The multiples of 20 are: 20, 40, 60, 80, 100, 120, 140, etc ...The multiples of 30 are: 30, 60, 90, 120, 150, etc ...The multiples of 40 are: 40, 80, 120, 160, etc. ...The lowest multiple common to 20, 30, and 40 is 120, so the LCM = 120