What is the least common multiple of 8, 6, and 12?
You're looking for the smallest number that 8, 6, and 12 share in common when you multiply each of them out. Start by multiplying 8 by 1, 2, 3, and so on.
Multiples of 8: 8 x 1 = 8; 8 x 2= 16; 8 x 3 = 24; 8 x 4 = 32
Now try multiples of 6: 6 x 1 = 6; 6 x 2 = 12; 6 x 3 = 18; 6 x 4 = 24
Finally, run through the same process with 12: 12 x 1 = 12; 12 x 2 = 24; 12 x 3 = 36; 12 x 4 = 48
See anything that pops out as familiar in all three lists? The number 24 shows up as a multiple of 8, 6, and 12. That's your least (or lowest) common multiple. To double-check the answer, try dividing 24 by each of the numbers. 24 ÷ 8 = 3; 24 ÷ 6 = 4; 24 ÷ 12 = 2.
Your least common multiple will never be smaller than the largest number in your series. For example, what's the least common multiple for 9 and 20? (Hint: The number is at least three digits!)