Electromagnetism

There are two solid spheres of radius $2R$ and $R$ of non-uniform charge density $R>1$ . The distance between their centre is $d$ . There is a point between their centre at which the net electric field is zero $0.$ Their charge densities are given as,

For bigger sphere, $\rho_{(r)} = \dfrac{A}{r}$ ,

For smaller sphere, $\rho_{(r)} = \dfrac{A}{r^2}$ , where $r$ is the distance from the centre of sphere.Suppose the required point is at $x$ distance from bigger sphere and $y$ distance from smaller sphere. Then $\dfrac{x}{y},$