\textbf{195-} If we perform Young's double-slit experiment with violet light, the width of each bright fringe is $x$, and if we perform the same experiment with yellow light, the width of each bright fringe is $x'$. If the slit separation with violet light is $1.5$ times the slit separation with yellow light, then $\dfrac{x'}{x}$ is?
(1) $\dfrac{2}{3}$ \hfill (2) $\dfrac{3}{2}$ \hfill (3) $2$ \hfill (4) $4$