21/(2*pi) = a radius of about 3.342253805 units
A circle with a radius of 21 inches has a circumference of 131.95 inches.
A circle with a radius of 21 units has a circumference of 131.95 units.
The radius of any circle is the straight line distance from the centre of the circle to any point on the circumference of the circle. The radius being 21 cm makes no difference to the definition of the radius; it just means that the straight line distance from the centre of that circle is 21cm away from any point on the circumference of that circle. The radius of a circle with a radius of 21 cm is 21 cm.
The circumference of a circle with a 2pi radius is: 39.58
If a circle circumference is 30 the radius is: 4.77
A circle with a radius of 21 inches has a circumference of 131.95 inches.
A circle with a radius of 21 meters has a circumference of 131.95 meters.
A circle with a radius of 21 units has a circumference of 131.95 units.
The circumference is 42pi, or approximately 131.946864
The radius is 3.34 units.
132cm
C = 131.95
The radius of any circle is the straight line distance from the centre of the circle to any point on the circumference of the circle. The radius being 21 cm makes no difference to the definition of the radius; it just means that the straight line distance from the centre of that circle is 21cm away from any point on the circumference of that circle. The radius of a circle with a radius of 21 cm is 21 cm.
the radius is 10.5 inches. * * * * * Wrong! Circumference = 2*pi*Radius Or, Radius = Circumference/(2*pi) So circumference = 21 inches implies radius = 3.34 inches (to 3 sf)
65.94 feet
The perimeter which is the circumference of a circle is: pi*diameter or 2*pi*radius
Circumference = 2Ï€r = 42Ï€ so r = 21 units.