Rotational Motion

Two identical spheres each of mass \(2 \mathrm{~kg}\) and radius \(50 \mathrm{~cm}\) are fixed at the ends of a light rod so that the separation between the centers is \(150 \mathrm{~cm}\). Then, moment of inertia of the system about an axis perpendicular to the rod and passing through its middle point is \(\frac{x}{20} \mathrm{~kg} \mathrm{m^{2 }}\), where the value of \(x\) is ___________.