Math CentralQuandaries & Queries


Question from Ray:

How do you find the circumference or radius of an area presuming it is a circle. Or in other words how do you find the c or r given only the area is 50 sq metres


The area of a circle is given by area = π r2 where r is the radius and π is approximately 3.1416. Thus if the area is 50 sq metres then

50 = π r2


r = √(50/π) = 3.99 metres

Once you know the radius you can find the circumference from the expression

circumference = 2 π r.


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