This math topic focuses on calculating the inner radius of a circle donut, using given values for the outer radius and the total area of the donut. Each problem provides a different combination of outer radius and area, and students are asked to determine the matching inner radius from multiple choice options. This involves understanding the geometric relationships within circular figures, specifically applying the formulas for the areas of circles to find unknown dimensions within composite shapes like donuts. These problems fall under an introductory unit on the area of circles, sectors, and donuts in geometry.

Work on practice problems directly here, or download the printable pdf worksheet to practice offline.