document.write( "Question 262981: There are two circles, one circle is inscribed and another circle is circumscribed over a square. What is the ratio of area of inner to outer circle? \n" ); document.write( "
Algebra.Com's Answer #193730 by ajmisra(4)![]() ![]() ![]() You can put this solution on YOUR website! It quite easy to solve this one.. \n" ); document.write( "Let each of the sides of the square be 'x' \n" ); document.write( "Then, by pythagoras theorem we know the diagonal of the spuare would be \n" ); document.write( "square root of (x^2 + x^2) i.e. (sq root of 2)times 'x'\r \n" ); document.write( "\n" ); document.write( "Now the inscribed circle is within the bounds of the sqaure, hence has a radius of half the sqaure's sides; i.e radius of inscribed circle is 'x/2' \n" ); document.write( "Thus area of inscribed circle is 'pie' times (x/2)^2\r \n" ); document.write( "\n" ); document.write( "For the circumscribed circle the diameter of the circle would be the diagonal of the square which we know to be (sq root of 2)times 'x' \n" ); document.write( "Hence radius of this circumscribed circle would be 1/2 the diameter\r \n" ); document.write( "\n" ); document.write( "Thus area of this circumscribed circle is 'pie' times {1/2 [(sq root of 2)times 'x']}^2\r \n" ); document.write( "\n" ); document.write( "Taking the required ratio we have,\r \n" ); document.write( "\n" ); document.write( "Inscribed Circle Area/Circumscribed Circle Area =\r \n" ); document.write( "\n" ); document.write( "{pie' times (x/2)^2} /{'pie' times {1/2 [(sq root of 2)times 'x']}^2}\r \n" ); document.write( "\n" ); document.write( "i.e. cancelling 'pie' in numerator and denominator we have \n" ); document.write( " {(x^2)/4} / [(sq root of 2)^2 times x^2]/4 \n" ); document.write( "further removing the common '4' denominators we have \n" ); document.write( "x^2 / (sq root of 2)^2 times x^2\r \n" ); document.write( "\n" ); document.write( "Further reducing would give us \n" ); document.write( "x^2 / 2 times x^2 (since (sq root of 2)^2 is simply 2)\r \n" ); document.write( "\n" ); document.write( "Again reducing getting rid of x^2 from numerator and denominator gives us: \n" ); document.write( "1/2\r \n" ); document.write( "\n" ); document.write( "Thus, \n" ); document.write( "Inscribed Circle Area/Circumscribed Circle Area = 1/2 as required! \n" ); document.write( " |