What is the smallest perfect square that is divisible by 6, 12, and 18?

Find the LCM of 6, 12, and 18:

Prime factors:
6 = $2 \times 3$
12 = $2^2 \times 3$
18 = $2 \times 3^2$

LCM = $2^2 \times 3^2 = 36$

Now, 36 is already a perfect square:

$36 = 6^2$

Final Answer: 36