The product of three consecutive even numbers when divided by 8 is 720. The product of their square roots is :

Let the numbers be x, x + 2 and x + 4
Then,
$$\eqalign{ & \Leftrightarrow \frac{{x\left( {x + 2} \right)\left( {x + 4} \right)}}{8} = 720 \cr & \Leftrightarrow x\left( {x + 2} \right)\left( {x + 4} \right) = 5760 \cr & \therefore \sqrt x \times \sqrt {\left( {x + 2} \right)} \times \sqrt {\left( {x + 4} \right)} \cr & = \sqrt {x\left( {x + 2} \right)\left( {x + 4} \right)} \cr & = \sqrt {5760} \cr & = 24\sqrt {10} \cr} $$