Let $f:\left(0,\infty \right)\to R$ be such that  $f(x/y)=f\left(x\right)/\text{}f\left(y\right),$ for all $x,y\in (0,\infty )$  ,$f\left(\frac{1}{2}\right)=\frac{1}{4}$,If  $y=y\left(x\right)$ satisfies the differential equation, $\frac{dy}{dx}=f\left(x\right)$  such that y(1)=1/3  then $y\left(3\right)$ is equal to