



 
Amanda, The area of a circle is given by the formula A = π r^{2}, where A is the area and r is the radius. The circumference of a circle is C = 2 π r. If we "solve for r" in the second equation, we have r = C / (2 π ). Now we use this to replace r in the first equation: A = π [ C / (2 π ) ]^{2}. When we simplify this, we get A = C^{2} / (4 π). Now you can put your value of C into this equation and find A. Remember, π is about 3.1416. Stephen La Rocque.  


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