## Diameter of a circle

The Diameter of a circle or sphere is equal to 2 times the Radius.

$\text"Diameter" = 2 ⋅ \text"Radius"$

## Circumference of a circle

The Circumference of a circle or a sphere is equal to 6.2832 times the Radius.

$\text"Circumference" = 6.2832 ⋅ R$

$C = 2 ⋅ π ⋅ R$

The Circumference of a circle or a sphere is equal to 3.1416 times the Diameter.

$\text"Circumference" = 3.1416 ⋅ \text"Diameter"$

$C = π ⋅ D$

## Radius of a circle

The Radius of a circle or sphere is equal to the Diameter divided by 2.

$R = D / 2$

## Area of a circle

The Area of a circle is equal to the Radius of the circle multiplied by the Radius and then this number multiplied by 3.1416.

$\text"Area" = R^2 ⋅ π$

$\text"Area" = R ⋅ R ⋅ 3.1416$

This number will be in square inches or square millimeters, depending on the measurement system used.

The Area of a circle is equal to the Diameter of the circle multiplied by the Diameter and then this number multiplied by 3.1416 and then this total is divided by 4.

$\text"Area" = D ⋅ D ⋅ 3.1416 / 4$

$\text"Area" = D^2 ⋅ π/ 4$

## Area of a Cylinder

This number will be in square inches or square millimeters, depending on the measurement system used.

The Area of a Cylinder is equal to 6.2832 ( 2 × π) times the radius of the Cylinder, times the sum of the Radius plus the Height.

$\text"Area" = 2 ⋅ 3.1416 ⋅ R ⋅ ( R + H )$

$\text"Area" = 2 ⋅ π ⋅ R ⋅ ( R + H )$

This number will be in square inches or square millimeters, depending on the measurement system used.

## Volume of Cylinder

The Volume of Cylinder is equal to the radius of the Cylinder, multiplied by the Radius, and this number multiplied by by 3.1416, then this number is multiplied by the length of the Cylinder.

$\text"Volume" = 3.1416 ⋅ R ⋅ R ⋅ H$

$\text"Volume" = π ⋅ R^2 ⋅ H$

This number will be in cubic inches or cubic millimeters, depending on the measurement system used.

## Area of a Sphere

The Area of a Sphere is equal to the Square of the Radius of the sphere multiplied by 12.566 ( 4 × π) or Pi times the Diameter squared ( π × D × D ).

$\text"Area" = 12.566 ⋅ R ⋅ R$

$\text"Area" = 4 ⋅ π ⋅ R^2$

$\text"Area" = π ⋅ D^2$

## Volume of a Sphere

The Volume of a Sphere is equal to the Radius of the Sphere, multiplied by the Radius again. Then this number is multiplied by the radius again. Then this number is multiplied by 12.566. and the result is divided by 3.

$\text"Volume" = 12.566 ⋅ R ⋅ R ⋅ R / 3$

$\text"Volume" = 4 ⋅ π ⋅ R ⋅ R ⋅ R / 3$

$\text"Sphere Volume" = 4/3 ⋅ π ⋅ r^3 = ( π ⋅ d^3)/6$

This number will be in cubic inches or cubic millimeters, depending on the measurement system used.