A smaller circle touches a bigger circle internally and also passes through the center 'O' of the bigger circle. If the area of the smaller circle is 192 cm², the area of the bigger circle (in cm²) is:

768

We know that,

Area of a circle = πr² 

We have,

The area of the smaller circle = 192 cm²

Let the radius of the smaller circle be r.

So, the radius of the bigger circle = 2r

Area of the bigger circle = π (2r)²

πr² = 192

= 4 × πr² = 4 × 192

= π × (2r)² = 768 cm²