A uniform disc of radius R is put over another uniform disc of radius 2R of the same thickness and density. The peripheries of the two discs touch each other. Locate the centre of mass of the system.

Explanation

To locate the center of mass of the system consisting of two uniform discs, we can follow these steps:

### Step 1: Understand the configuration of the discs
We have two discs:
- Disc A (smaller disc) with radius \( R \)
- Disc B (larger disc) with radius \( 2R \)

The discs are stacked such that their peripheries touch each other. The center of Disc B is considered as the origin (0,0) in our coordinate system.
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