document.write( "Question 280316: A square has twice the perimeter of a circle . the ratio of the area of the square to the area of the circle is\r
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document.write( "A 4 b pi c 1/pi d 16/pi e none of these \r
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Algebra.Com's Answer #203773 by dabanfield(803)![]() ![]() ![]() You can put this solution on YOUR website! A square has twice the perimeter of a circle . the ratio of the area of the square to the area of the circle is \n" ); document.write( "A 4 b pi c 1/pi d 16/pi e none of these \r \n" ); document.write( "\n" ); document.write( "Let x be a side of the square. The perimeter of the square is then 4*x. The perimeter (i.e. circumference) of the circle then is (1/2)*4x = 2x. The circumference is also given by pi*diameter = pi*2*r where r is the radius. \r \n" ); document.write( "\n" ); document.write( "So we have pi*2*r = 2*x and \n" ); document.write( "r = 2x/2pi = x/pi\r \n" ); document.write( "\n" ); document.write( "The area of the square is x*x = x^2 \n" ); document.write( "The area of the circle with radius r is pi*r^2\r \n" ); document.write( "\n" ); document.write( "The ratios of the two areas is area of square/area of circle.\r \n" ); document.write( "\n" ); document.write( "Using the fact that r = x/pi we the ratios become:\r \n" ); document.write( "\n" ); document.write( "x^2/(pi*(x/pi)^2) =\r \n" ); document.write( "\n" ); document.write( "x^2/(pi*(x^2/pi^2))=\r \n" ); document.write( "\n" ); document.write( "(x^2/x^2)/(pi/pi^2)= \n" ); document.write( "1/pi \n" ); document.write( " |