A cone is a three-dimensional object with a circular base. As the cone grows upward, the size of the circle lessens until it becomes a single point at the top of the cone. A radius is the distance from the circle's middle to its perimeter, which is known as its circumference. The radius of a cone is the radius of its circular base. You can find a radius through its volume and height.

### Step 1

Multiply the volume by 3. For example, the volume is 20. Multiplying 20 by 3 equals 60.

### Step 2

Multiply the height by π, which is a numeric constant that begins 3.14 and never terminates. For this example, the height is 4, and 4 multiplied by π equals 12.566.

### Step 3

Divide the tripled volume by the product of the height and π. For this example, 60 divided by 12.566 equals 4.775.

### Step 4

Find the square root of the result from Step 3. For this example, the square root of 4.775 equals 2.185. The radius is 2.185.

#### Things You Will Need

- Calculator

#### References

- "Basic Math and Pre-algebra"; Jerry Bobrow; 1995
- "The Complete Idiot's Guide to Geometry"; Denise Szecsei; 2004

#### Photo Credits

- Thinkstock/Comstock/Getty Images