Answer:
60
Step-by-step explanation:
LCM = least common multiple, the smallest product all the numbers have in common.
Let's find the multiples of the numbers:
5: 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60
6: 12, 18, 24, 30, 36, 42, 48, 54, 60, 66, 72
12: 12, 24, 36, 48, 60, 72, 84, 96, 108, 120
We can see that the smallest multiple all these numbers have in common is 60.