document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=166271>Question 166271</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Three lighthouses on three nearby islands flash their lights every evening beginning at 8:35pm.  On one island, the ligh flashes every 45 seconds.  The lighthouse on the second island has a light that flashes every 2 minutes.  The third lighthouse flashes a light every 1 1/4 minutes.  At what time will all three lights flash together again?  \r<BR>\n" );
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document.write( "This is a problem of the week just given to my child on a single piece of paper.\r<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 #122552 by </B><A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><B>ankor@dixie-net.com(22740)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><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/cgi-bin/show-face.mpl?user=ankor@dixie-net.com><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=122552\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Three lighthouses on three nearby islands flash their lights every evening <BR>\n" );
document.write( "beginning at 8:35pm. On one island, the ligh flashes every 45 seconds. <BR>\n" );
document.write( "The lighthouse on the second island has a light that flashes every 2 minutes. <BR>\n" );
document.write( "The third lighthouse flashes a light every 1 1/4 minutes. <BR>\n" );
document.write( "At what time will all three lights flash together again?<BR>\n" );
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document.write( "Convert 2 min to seconds and 1.25 min to seconds. <BR>\n" );
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document.write( "So we have:<BR>\n" );
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document.write( "Lt1 = 45; Lt2 = 120; Lt3 = 75<BR>\n" );
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document.write( "Prime factor each:<BR>\n" );
document.write( "45: 3,3,5,<BR>\n" );
document.write( "120: 2,2,2,3,5<BR>\n" );
document.write( "75: 3,5,5<BR>\n" );
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document.write( "Lcm of all three: 2,2,2,3,3,5,5  Multiply this: 1800 secs they will all Flash<BR>\n" );
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document.write( "1800/60 = 30 min: At 9:05Pm this should occur<BR>\n" );
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