2018-10-12 15:37:13 -04:00
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---
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title: Surface Area of a Sphere
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---
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## Surface Area of a Sphere
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2019-03-11 12:02:25 -07:00
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The surface area **A** of a sphere with radius **r** may be calculated by the following formula:
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#### A = 4πr²
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where **π** is the ratio of a circle's circumference to its diameter (<em>π</em> ≈ 3.14159).
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2018-10-12 15:37:13 -04:00
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2019-03-11 12:02:25 -07:00
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### Example:
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*Problem:* Given a sphere with a radius of 11 inches, find its surface area.
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2018-10-12 15:37:13 -04:00
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2019-03-11 12:02:25 -07:00
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*Solution:* A = 4×*π*×11² ≈ 1520.5 square inches
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2018-10-12 15:37:13 -04:00
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#### More Information:
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2019-03-11 12:02:25 -07:00
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- [Wikipedia](https://en.wikipedia.org/wiki/Sphere)
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