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Popular Word Problems >

The area of a circle is 81𝜋 square feet. What is the circumference?

Solution

T h e a re a o f a c i rc l e i s 81​𝜋 s q u a re f ee t . Wha t i s t h e c i rc u m f ere n ce ?

Solution

c i rc u m f ere n ce : 18 π f t

+1

Decimal

56.54866 \dots

Solution steps

Given:

a re a : 81 π f t^{2}

Radius given

A re a = 81 π : r = 9

Circle circumference given

r = 9 : C = 18 π

c i rc u m f ere n ce : 18 π f t

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