document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=113267>Question 113267</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The intensity I of light varies inversely as the square of the distance D from the source. If the intensity of illumination on a screen 5 ft from a light is 3 foot-candles, find the intensity on a screen 15 ft from the light.\r<BR>\n" );
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document.write( "This is what I did...\r<BR>\n" );
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document.write( "y=k/x^2\r<BR>\n" );
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document.write( "3=k/5^2\r<BR>\n" );
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document.write( "3=k/25\r<BR>\n" );
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document.write( "k=75\r<BR>\n" );
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document.write( "y=75/x^2\r<BR>\n" );
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document.write( "y= 75/15^2\r<BR>\n" );
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document.write( "=75/225\r<BR>\n" );
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document.write( "=.333 footcandles\r<BR>\n" );
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document.write( "Is this correct? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #82427 by </B><A HREF=/tutors/aboutme.mpl?userid=Earlsdon><B>Earlsdon(6294)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Earlsdon><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=82427\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Your answer is absolutely correct!<BR>\n" );
document.write( "But I am puzzled as to why you did not use the same letters for the unknowns as given in the problem?\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=I+=+k%2FD%5E2 ALIGN=MIDDLE  ALT=\"I+=+k%2FD%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" > </SPAN>\n" );
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