Question 1148876
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A square rock garden with sides of 90 feet is placed in the middle of a circular grass yard. 
If the circumference of the yard is 520 feet, then how much area is covered by grass?
For all calculations involving π, use π≈3.14.
Hint: Be careful that you do not do any rounding on answers until the very end of a problem part, or you could create rounding error.
a) Amount of area covered by grass, measured in square feet = Blank square feet.
DO NOT TYPE COMMAS. Round your answer to 2 decimal places as needed.
b) Amount of area covered by grass, measured in square yards = blank square yards.
Round your answer to 2 decimal places as needed
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        Calculations in the post by @addingup are fatally wrong.

        I came to bring a correct solution.



<pre>
Area of the square is 90^2 = 8100 sq. feet.


Area of the circle is  {{{pi*r^2}}} = {{{pi*(520/(2*pi))^2}}} = {{{520^2/(4*pi))}}} = {{{520^2/(4*3.14)}}} = 21528.66 sq. feet.


(a) The area covered by grass is  21528.66 - 8100 = 13428.66 sq. feet.


(b) Measured in square yards, this area is  {{{13428.66/3^2}}} = 1119.06 sq. yards  (rounded).
</pre>

Solved correctly.