Circles: Circumference & Area (Set 3) Worksheet

Sample problems

Use $C=2\pi r=\pi d$ for circumference and $A=\pi r^2$ for area; for a sector or arc, scale by $\frac{\theta }{360}$. Leave every answer in terms of $\pi$ (do not use a decimal approximation such as $3.14$). Include units.

1. 1. A circle has radius $11$ m. Find its circumference, leaving your answer in terms of $\pi$.
2. 2. A circle has diameter $18$ cm. Find its area, leaving your answer in terms of $\pi$.
3. 3. The circumference of a circle is $44\pi$ in. Find its radius and its diameter.
4. 4. The area of a circle is $144\pi$ square m. Find its radius.

Plus 10 more problems and a full answer key in the PDF.