4060, 8120, 12180.
20, 40, 60...
15 & 20 have an infinite number of Common Multiples; the first three are 60, 120 and 180.
10, 20 and 30.
20, 40, 60
What are the first three common multiples of four and five
10, 20, 30
40, 80 & 120.
140, 280, 420
140, 280, 420
10, 20, 30
20, 40, and 60.
20, 40, 60