From a solid sphere of radius 2 m a sphere of radius 1 m is removed. The new centre of mass from C1 is
At c1 mass of the whole surface can be imagined.
At c2 mass of the removed sphere can be imagined.
∴ xcm = V1x1+V2x2V1+V2
xcm=43πr31(0)−43πr32(1)343πr31−43πr32=−r32r31−r32=−18−1=−17m
∴ The new centre of mass is \frac 17 m from C1 towards left.