document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=149521>Question 149521</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The surface areas of two cubes are in the ratio of 49:81. If the volume of the smaller cube is 20, what is the volume of the larger cube?<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #109702 by </B><A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><B>jim_thompson5910(35256)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><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=109702\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Since the ratio of the surface areas is 49:81, this means that \r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=ratio_surface_area=49%2F81 ALIGN=MIDDLE  ALT=\"ratio_surface_area=49%2F81\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Now simply take the square root of the fraction to get the ratio of the sides.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sqrt%2849%2F81%29=sqrt%2849%29%2Fsqrt%2881%29=7%2F9 ALIGN=MIDDLE  ALT=\"sqrt%2849%2F81%29=sqrt%2849%29%2Fsqrt%2881%29=7%2F9\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "So the ratio of the sides is 7:9\r<BR>\n" );
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document.write( "Now simply cube <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=7%2F9 ALIGN=MIDDLE  ALT=\"7%2F9\"   DISABLED_style= \"max-width:90%; height:auto;\" > to get the ratio of the two volumes\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=7%5E3%2F9%5E3=343%2F729 ALIGN=MIDDLE  ALT=\"7%5E3%2F9%5E3=343%2F729\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Now let x=volume of the larger cube\r<BR>\n" );
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document.write( "Since the ratio of the two volumes, this means that we can say\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=20%2Fx=343%2F729 ALIGN=MIDDLE  ALT=\"20%2Fx=343%2F729\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=20=%28343%2F729%29%2Ax ALIGN=MIDDLE  ALT=\"20=%28343%2F729%29%2Ax\"   DISABLED_style= \"max-width:90%; height:auto;\" > Multiply both sides by x\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=20%2A729=343%2Ax ALIGN=MIDDLE  ALT=\"20%2A729=343%2Ax\"   DISABLED_style= \"max-width:90%; height:auto;\" > Multiply both sides by 729\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=14580=343%2Ax ALIGN=MIDDLE  ALT=\"14580=343%2Ax\"   DISABLED_style= \"max-width:90%; height:auto;\" > Multiply\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=14580%2F343=x ALIGN=MIDDLE  ALT=\"14580%2F343=x\"   DISABLED_style= \"max-width:90%; height:auto;\" > Divide both sides by 343\r<BR>\n" );
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document.write( "So our answer is  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=14580%2F343 ALIGN=MIDDLE  ALT=\"x=14580%2F343\"   DISABLED_style= \"max-width:90%; height:auto;\" > which is approximately <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=42.51 ALIGN=MIDDLE  ALT=\"x=42.51\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "So the volume of the larger cube is 42.51 </SPAN>\n" );
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