Answer
$\sqrt{3}$
Work Step by Step
Let $A=(3,4,5)$ and $B=(2,3,4)$ be the two given points.
The distance between two points can be calculated as: $|AB|=\sqrt{(x-x_0)^2+(y-y_0)^2+(z-z_0)^2}$
Thus, we have
$|AB|=\sqrt{(2-3)^2+(3-4)^2+(4-5)^2}=\sqrt {1+1+1}=\sqrt{3}$
