Answer:
65.94cm
Step-by-step explanation:
The two equivalent equations to find the circumference of a circle are:
Circumference = 2 * pi * radius
Circumference = pi * diameter
Since the diameter of the circle is given, in order to find circumference, plug in 21cm into the 2nd equation:
Circumference = pi * diameter = pi * 21 cm = 3.14 * 21 = 65.94 cm
