A circular disc of radius $$R$$ is removed from a bigger circular disc of radius $$2R$$ such that the circumferences of the discs coincide. The centre of mass of the new disc is $$\alpha/R$$ from the centre of the bigger disc. The value of $$\alpha$$ is

A

$$1/3$$

B

$$1/2$$

C

$$1/6$$

D

$$1/4$$