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the area of circle B is 36 times greater than the area of circle A. The radius of circle B is 30. what is the radius of circle A

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Ab = pi*r^2 = 3.14 * 30^2 = 2837.4 = Area of B.

Ab = Aa + 30Aa = 2827.4
31Aa = 2827.4
Aa = 91.2.

Aa = pi*r^2 = 91.2
r^2 = 91.2 / pi = 29.03
r = 5.4 = Radius of circle A.

• math -

Correction: Ab = 2827.4.

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