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Area of a Circle

Also known as πr² · area of a round shape

A=πr2A = \pi r^{2}

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The area of a circle grows with the square of its radius — double the radius and you quadruple the area. This is why pipe capacity climbs so quickly with diameter: a 2-inch pipe carries four times the cross-section of a 1-inch pipe.

Area of a Circle
A=πr2A = \pi r^{2}
Where
  • AA= Area
  • rr= Radius
Missing one of these? Work it out first, then come back