Circle Tool

Drag the radius slider. Watch the diameter and circumference change with it.

Challenge

Radius (r)

5 cm

Diameter (d = 2 × r)

10 cm

Circumference (C ≈ π × d)

31.4 cm

C ÷ d (the ratio)

3.14 ≈ π

Every circle gives the same answer.

Set the radius

148 cm

Think about this