document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=842929>Question 842929</A>: <I><SPAN STYLE=\"word-break: break-all;\">  One light house flashes every 10 seconds, and a second lighthouse flashes every 12 seconds. If they both flash at the same moment, how long will it be until they will flash together again? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #507800 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39617)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><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=507800\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Sixty seconds.\r<BR>\n" );
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document.write( "At a very low level you can simulate this way:\r<BR>\n" );
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document.write( "Starting at time 0,<BR>\n" );
document.write( "10 sec______________12 sec<BR>\n" );
document.write( "10__________________24<BR>\n" );
document.write( "20__________________36<BR>\n" );
document.write( "30__________________48<BR>\n" );
document.write( "50__________________60<BR>\n" );
document.write( "60___________\r<BR>\n" );
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document.write( "The first or smallest time point they have in common is 60 seconds.<BR>\n" );
document.write( "This really is just like looking for a Lowest Common Denominator for fractions. </SPAN>\n" );
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