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Topic: Please help me with the following question
Replies: 78   Last Post: Mar 25, 2013 1:38 AM

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Robert Hansen

Posts: 7,703
From: Florida
Registered: 6/22/09
Re: Please help me with the following question
Posted: Mar 11, 2013 3:59 PM
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On Mar 11, 2013, at 11:49 AM, Joe Niederberger <niederberger@comcast.net> wrote:

>> At the same time I knew that the final step had to involve 3 coins or less
>
> Except that's not true.


The balanced strategy gives

1. AAAA BBBB CCCC <- 3 groups of 4 coins.
2. ABBB CCCB <- This is the next weighing if in step 1 AAAA != BBBB (otherwise it is trivial)
3. AB or BBB <- this can be resolved in one weighing AND also knowing the result of step 2.

You cannot end up with a group of 4 coins in step 3 and in one more weighing know which single coin is counterfeit, even if you know which way it leans.

Bob Hansen


Date Subject Author
2/24/13
Read Please help me with the following question
hydraflap
2/24/13
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Richard Strausz
2/25/13
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James Elander
2/27/13
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Wayne Bishop
3/1/13
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GS Chandy
3/1/13
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GS Chandy
3/5/13
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johnykeets
3/7/13
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Joe Niederberger
3/7/13
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Robert Hansen
3/7/13
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Joe Niederberger
3/7/13
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Joe Niederberger
3/7/13
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Robert Hansen
3/7/13
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Joe Niederberger
3/7/13
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Joe Niederberger
3/7/13
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Robert Hansen
3/7/13
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Robert Hansen
3/7/13
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GS Chandy
3/7/13
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Robert Hansen
3/7/13
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GS Chandy
3/7/13
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GS Chandy
3/7/13
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Robert Hansen
3/7/13
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GS Chandy
3/7/13
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GS Chandy
3/7/13
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Joe Niederberger
3/7/13
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Joe Niederberger
3/8/13
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GS Chandy
3/8/13
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GS Chandy
3/8/13
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GS Chandy
3/8/13
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GS Chandy
3/8/13
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GS Chandy
3/8/13
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Robert Hansen
3/8/13
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Joe Niederberger
3/8/13
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Robert Hansen
3/8/13
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Joe Niederberger
3/8/13
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Robert Hansen
3/8/13
Read Re: Please help me with the following question
Joe Niederberger
3/8/13
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Robert Hansen
3/8/13
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Joe Niederberger
3/9/13
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Robert Hansen
3/8/13
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Joe Niederberger
3/8/13
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Joe Niederberger
3/9/13
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GS Chandy
3/9/13
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Robert Hansen
3/8/13
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GS Chandy
3/9/13
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GS Chandy
3/8/13
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GS Chandy
3/9/13
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Joe Niederberger
3/9/13
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Robert Hansen
3/10/13
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Robert Hansen
3/9/13
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GS Chandy
3/10/13
Read Re: Please help me with the following question
GS Chandy
3/10/13
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GS Chandy
3/10/13
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Joe Niederberger
3/10/13
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Robert Hansen
3/10/13
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GS Chandy
3/11/13
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Robert Hansen
3/11/13
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Joe Niederberger
3/11/13
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Robert Hansen
3/11/13
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Robert Hansen
3/11/13
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Joe Niederberger
3/11/13
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Robert Hansen
3/11/13
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Joe Niederberger
3/11/13
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Robert Hansen
3/11/13
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Robert Hansen
3/12/13
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Joe Niederberger
3/12/13
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GS Chandy
3/13/13
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GS Chandy
3/13/13
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Robert Hansen
3/13/13
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Joe Niederberger
3/13/13
Read Re: Please help me with the following question
Robert Hansen
3/13/13
Read Re: Please help me with the following question
Joe Niederberger
3/14/13
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Robert Hansen
3/14/13
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Robert Hansen
3/15/13
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GS Chandy
3/14/13
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Joe Niederberger
3/14/13
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Robert Hansen
3/14/13
Read Re: Please help me with the following question
Joe Niederberger
3/15/13
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GS Chandy
3/25/13
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