Answer:

Multiples that are common to two or more numbers are said to be common multiples.

The multiple of 4 are 8 = 2 x 4, 12 = 3 x 4, 16 = 4 x 4 etc.

The multiple of 6 are 12 = 2 x 6, 18 = 3 x 6, 24 = 4 x 6, etc.

12 is a common multiple of 4 and 6 and so is 36 etc.