Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.2 8/28/84; site lll-crg.ARPA Path: utzoo!watmath!clyde!bonnie!akgua!mcnc!philabs!cmcl2!seismo!umcp-cs!gymble!lll-crg!muffy From: muffy@lll-crg.ARPA (Muffy Barkocy) Newsgroups: net.puzzle Subject: Re: Yet another weighing problem Message-ID: <538@lll-crg.ARPA> Date: Sun, 21-Apr-85 18:20:45 EST Article-I.D.: lll-crg.538 Posted: Sun Apr 21 18:20:45 1985 Date-Received: Wed, 24-Apr-85 02:36:51 EST References: <5755@duke.UUCP> <419@talcott.UUCP> Reply-To: muffy@lll-crg.UUCP (Muffy Barkocy) Organization: Lawrence Livermore Labs, CRG group Lines: 28 In article <419@talcott.UUCP> jak@talcott.UUCP (Joe Konstan) writes: >> A piece of gold weighing 40 pounds was dropped and broken into 4 >> pieces. It was broken in such a way that you can, using the 4 >> pieces, weigh anything weighing from 1 up to 40 pounds. For example >> something weighing 5 pounds could be weighed using one piece of >> gold weighing 15 pounds and another weighing 10 pounds. > >> How about generalizing it, lets assume that the gold originally >> weighed K pounds and was broken into n pieces, what are the weights >> of the n pieces given that the above property still holds ? >> >> Note: I do not know (yet) the solution to the second one. > >In general, we want to break it into blocks of 3^n for n going from >0 up as high as possible. I think that leaving the leftover as just one >block will be good enough to weigh everything, by always using that >block for weights above it. > >Mithrandir >jak@talcott Yes, but...suppose the problem is: break a 40-lb block into *5* pieces? Then, using 3^n, we get 1 3 9 27 *0*. How would you do this? I assume that any of them could just be broken in two, but your answer should have included this case. Muffy