Question

A circle has a radius of 3 cm. How does the circumference of the circle compare to the area? Drag and drop a phrase to correctly complete the sentence.

Answer 1

The circumference is about 3.14 ($\pi$) times bigger than twice the radius.  Mathematically, this can be writted as $C = 2 \pi r$, where C equals the circumference and r equals the radius, or $C = \pi d$ where C equals the circumference and d equals the radius.