The first few multiples of 8 are: 8, 16, 24, 32, 40, and 48. The first multiples of 12 are: 12, 24, 36, 48, 60, and 72.
Common multiple of 8 and 12 are 24 and every subsequent multiple of 24.
As 8×3=24
12×2=24
So 24 is a common multiple of 8 and 12 this means the other common multiples of 8 and 12 are the multiples of 24 like 48, 72, 96 etc.