document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=137510>Question 137510</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A penny has a diameter of 23.05mm and a thinness of 1.45mm. Find the surface area of the conin to the nearest hundredth. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #100611 by </B><A HREF=/tutors/aboutme.mpl?userid=vleith><B>vleith(2983)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=vleith><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=100611\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> What are the surfaces on the coin?<BR>\n" );
document.write( "You have the front, the back and the rim. The front and back are the same -- just the area of a circle.\r<BR>\n" );
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document.write( "The rim (side) can be found using formulas for surface area of cylinders. OR, in this case, you can mentally \"unroll\" the side. Imagine making a vertical cut and then unrolling. What do you end up with? \r<BR>\n" );
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document.write( "Right, you end up a rectangle with sides of 1.45mm and the circumference of the circle making up the front/back.\r<BR>\n" );
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document.write( "Net, you have three areas\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=Surface+area+=+AreaFront+%2B+AreaBack+%2B+AreaSide ALIGN=MIDDLE  ALT=\"Surface+area+=+AreaFront+%2B+AreaBack+%2B+AreaSide\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A+=+2%2AAreaFront+%2B+AreaSide ALIGN=MIDDLE  ALT=\"A+=+2%2AAreaFront+%2B+AreaSide\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "The area of a circle is given by <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A=pi%2Ar%5E2 ALIGN=MIDDLE  ALT=\"A=pi%2Ar%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" > . we are given the diameter, so we need to divide by 2 to get the radius.\r<BR>\n" );
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document.write( "The area of a rectangle is given by <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A+=+Length%2AWidth ALIGN=MIDDLE  ALT=\"A+=+Length%2AWidth\"   DISABLED_style= \"max-width:90%; height:auto;\" >. We are given the width and need to calculate the length. The length is just the circumference. Circumference is given by <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=C=pi%2Ad ALIGN=MIDDLE  ALT=\"C=pi%2Ad\"   DISABLED_style= \"max-width:90%; height:auto;\" >.\r<BR>\n" );
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document.write( "Now you have everything you need.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A+=+2%2A%28pi%2A%2823.05%2F2%29%5E2%29++%2B+%28pi%2A23.05+%2A+1.45%29 ALIGN=MIDDLE  ALT=\"A+=+2%2A%28pi%2A%2823.05%2F2%29%5E2%29++%2B+%28pi%2A23.05+%2A+1.45%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "You can it in from here </SPAN>\n" );
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