document.write( "Question 40018: I need to find the total surface area of a stand that was cut from a right circular cone (now called a frustum of a cone).\r
\n" ); document.write( "\n" ); document.write( "The height is 40 cm,bottom radius is 100 cm, and the top radius is 60 cm. \n" ); document.write( "
Algebra.Com's Answer #25418 by venugopalramana(3286)\"\" \"About 
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I need to find the total surface area of a stand that was cut from a right circular cone (now called a frustum of a cone).
\n" ); document.write( "The height is 40 cm,bottom radius is 100 cm, and the top radius is 60 cm. \r
\n" ); document.write( "\n" ); document.write( "let the original cone have AB as its altitude with A as vertex and B as the centre of the base.let C be a point on perimeter at the bottom.so AC is the slant height.
\n" ); document.write( "let D be the point on the axis at the top of the frustrum and E is point on slant height AC..we have
\n" ); document.write( "AB=H say
\n" ); document.write( "BC=radius at bottom = 100
\n" ); document.write( "DE radius at top=60
\n" ); document.write( "BD=frustum ht=40
\n" ); document.write( "AD=AB-BD=H-40
\n" ); document.write( "triangles ABC,ADE are similar.hence
\n" ); document.write( "AB/AD=BC/DE
\n" ); document.write( "H/(H-40)=100/60=5/3
\n" ); document.write( "3H=5H-200
\n" ); document.write( "2H=200
\n" ); document.write( "H=100
\n" ); document.write( "AD=100-40=60
\n" ); document.write( "so
\n" ); document.write( "volume of frustum= volume of full cone-volume of cut cone = (3.14/3){100*100*100-60*60*60}=820587 \n" ); document.write( "
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