SOLUTION: The area of a circle is given by the formula A=piR^2 where r is the radius. If increasing the radius of a circle by 1 inch gives the resulting circle an area of 100 times pi square

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Question 837955: The area of a circle is given by the formula A=piR^2 where r is the radius. If increasing the radius of a circle by 1 inch gives the resulting circle an area of 100 times pi square inches, what is the radius of the original circle

Found 2 solutions by josgarithmetic, stanbon:
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
You say, by description, pi%2A%28R%2B1%29%5E2=100%2Api, and you originally had pi%2AR%5E2=A;
You are taking A as a constant.

?
%28R%2B1%29%5E2=100, taking the increased radius equation and dividing left and right sides by pi.
R%2B1=10,
highlight%28R=9%29-----DONE.

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
The area of a circle is given by the formula A=piR^2 where r is the radius. If increasing the radius of a circle by 1 inch gives the resulting circle an area of 100 times pi square inches, what is the radius of the original circle
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Increased Area = pi(R+1)^2 = pi(R^2+2R+1) = piR^2 + pi(2R+1)
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Equation:
2R+1 = 100
2R = 99
R = 49.5 (original radius)
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Cheers,
Stan H.