Coins can be treated as discs. A dummy coin has an inner uniform solid disc with a diameter of 120.0 cm and an area density of 4.00 g/cm², which is encircled by a concentric ring with inner and outer diameters of 120.0 cm and 160.0 cm respectively and an area density of 2.50 g/cm². Find the coin's moment of inertia around an axis that passes through its center and is perpendicular to its plane.