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Find the Diameter of a circle

Simple instructions to find the diameter of a circle using the standard formula.

d=2r

These instructions are written in a simple format to explain how to find the diameter of a circle.

Instructions

The diameter of a circle is 2 x the radius and is basically the span of two radii across the circle's center point thus forming a horizontal line across the entire circle like the example shows. The formula is expressed as: d=2r , where d is the diameter and r is the radius.

For example, if r=4 , then you multiply 4 by 2. In this case the diameter would be 6. d=8

Simple rules to remember:

You always multiply the radius x 2 to get the diameter of a circle.

You can divide the diameter by 2 to get the radius of a circle if the diameter is known.