#define PI 3.1416
int r,area;
area=2*PI*r
The formula for the circumference of a circle is C = 2πr, where C is the circumference and r is the radius of the circle.
The radius of a circle with a circumference of 1000m is approximately 159.15 meters. This can be found using the formula C = 2πr, where C is the circumference and r is the radius. Rearranging the formula to solve for r gives r = C / (2π). Substituting the given circumference into the formula will give you the radius.
r = C/2π
Here are three: If you have the area - radius = sqrt( A/Pi ) If you have the diameter - radius = D/2 If you have the circumference - radius = (C/(2Pi))
C=2*pi*r Radius is the circumference of the circle divided by 2pi. Therefore, if the circumference was C then the following formula works out the radius: r=C/(2*pi)
The circumference of a circle is given by the formula C = 2πr where r is the radius. But, as the diameter is 2 x radius then the formula can be written C = πd where d is the diameter. In this example the circumference = 2π3 = 6π = 18.85 units.
The formula for the circumference of a circle is C = 2πr where r is the radius. This formula can also be expressed as C = πd where d is the diameter as the diameter is twice the radius. C = 15π = 47.12cm (2dp)
Use this formula where r is the radius: C = 2Pi(r)
The formula for the circumference (C) of a circle is C = 2πr where r is the radius. But, the diameter (D) of a circle is twice the radius so this formula can be written C = πD. C = π x 13 = 40.841 cm (3dp)
well, technically since the formula for circumference is c=2pir, technically r=c/2pi (otherwise stated as radius equals circumference divided by two pi).
To find the radius of a circle with a circumference of 121, you can use the formula for the circumference of a circle: C = 2πr, where C is the circumference and r is the radius. Given that the circumference is 121, you can plug this value into the formula and solve for the radius. Dividing 121 by 2π will give you the radius of the circle, which is approximately 19.24 units.
R is the radius, D is the diameter (twice the radius), 3.14 is PI, and C is circumference. The formula is: C = PI x D OR C = Pi x R x 2