62 lines
1.8 KiB
Markdown
62 lines
1.8 KiB
Markdown
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---
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title: Finding Circumference of a Circle When Given the Area
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---
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## Background information
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##### What is circumference?
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The length of enclosing boundary of a curved geometric figure.
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<hr>
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##### What is area?
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Area is measure of how much space there is on a flat surface.
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### Question: Find circumference of circle when area of circle is given?
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##### Steps:
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+ area of circle = π × r<sup>2</sup>, so we shall find radius of circle from with this formulae.
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+ circumference of circle = 2 × π r, and put radius in this formulae to calculate circumference.
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<pre>
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Example,
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Question) Find circumference of a circle with area = π<sup>3</sup>?
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Answer:
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By above steps,
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area = π × r<sup>2</sup>
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π<sup>3</sup> = π × π<sup>2</sup>
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by comparing, we get,
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radius, r = π
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Now put this value in formulae for circumference,
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cirucumference = 2 × π r
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= 2 × π π
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= 2 π<sup>2</sup>
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Hence, we found the answer.
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</pre>
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### Area (A) of a Circle
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A = π * radius<sup>2</sup>
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### Circumference (C) of a Circle
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C = 2 * π * radius
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## To find the Circumference of a Circle given the area
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1. Solve for the radius of the circle
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radius = (A / π)<sup>½</sup>
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2. Input the radius into the formula for the circumference and solve.
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C = 2 * π * (A / π)<sup>½</sup>
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#### More Information:
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[Area of a Circle](https://guide.freecodecamp.org/mathematics/area-of-a-circle)
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### Here are some cool illustrations
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#### Circumference
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#### Area
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