document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=26602>Question 26602</A>: <I><SPAN STYLE=\"word-break: break-all;\"> You have 13 coins, which all look alike. 12 coins weigh exactly the same, but the other is heavier. You have a pan balance.  Tell how to find the heavier coin in just 3 weighings.  Assume you can't tell just by holding the coins which on is heavier.\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 #14454 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=14454\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> You can do this in 3 or less weighings.\r<BR>\n" );
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document.write( "Weighing 1) Separate the coins into two equal piles of 6 coins each and put the left-over coin aside and place the two piles on the balance with 6 coins on each side.\r<BR>\n" );
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document.write( "If the scale balances, the heavy coin is the one you put aside.\r<BR>\n" );
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document.write( "Weighing 2) If the scale doesn't balance, take the six coins from the heavier side and divide them into two equal piles of three coins each and put the left-over coin aside. Now weigh the two 3-coin piles.<BR>\n" );
document.write( "If the scale balances, the heavy coin is the one you put aside.\r<BR>\n" );
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document.write( "Weighing 3) If the scale doesn't balance, take the three coins from the heavier side and divide them into two equal piles of 1 coin each and put the third coin aside.<BR>\n" );
document.write( "Now weigh the two 1-coin piles. If the scale balances, the heavy coin is the one you put aside.<BR>\n" );
document.write( "If the scale doesn't balance, the scale will indicate the heavier coin. </SPAN>\n" );
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