### Possible Answer

To find the lowest common multiple, list the multiples of each of the numbers and find the first they have in common. 10=10,20,30,40,50,60,70,80 ... - read more

The LCM of 15 and 20 is 60, which is the multiple of the combined prime factors of both numbers (2 x 2 x 3 x 5). - read more

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