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Photo
* * * * * 2 votes

The Magnetized Coin


Best Answer plainglazed, 09 February 2014 - 03:36 AM

Spoiler for three weighings...

Go to the full post


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13 replies to this topic

#1 TimeSpaceLightForce

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Posted 07 February 2014 - 11:23 AM

One of the 12 identical coins was magnetized so that it weighs
heavier on one face and lighter on the other when placed on
a certain weighing scale. But it weighs normal like the other coins
when it is standing balanced on its side or edge.

Find out which coin is it using the weighing scale 3 times.

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#68


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#2 phil1882

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Posted 07 February 2014 - 05:02 PM

Spoiler for

Edited by phil1882, 07 February 2014 - 05:03 PM.

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#3 TimeSpaceLightForce

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Posted 07 February 2014 - 05:45 PM

Spoiler for

Thanks for the math idea phil...lets say the coins normally weigh 1 unit or slightly heavy or lighter if magnetized..can  you give it another go for just 3 weighing?


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#4 phil1882

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Posted 08 February 2014 - 03:03 PM

hmm, 4 is possible not sure about 3.

Spoiler for

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#5 TimeSpaceLightForce

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Posted 08 February 2014 - 05:24 PM

..using the weighing scale 3 times includes determining which face of the magnetized coin is heavier or lighter.


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#6 plasmid

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Posted 08 February 2014 - 05:42 PM

Spoiler for Solution with one weighing

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#7 TimeSpaceLightForce

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Posted 08 February 2014 - 08:05 PM

Spoiler for
Hint : The 3 weighing solution is very easy..
 
 
 

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#8 plainglazed

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Posted 09 February 2014 - 03:36 AM   Best Answer

Spoiler for three weighings...


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#9 Brainy Binary

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Posted 09 February 2014 - 06:45 AM

 

Spoiler for
Hint : The 3 weighing solution is very easy..
 

Spoiler for no uncertainty 2 weighing


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#10 TimeSpaceLightForce

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Posted 09 February 2014 - 09:25 AM

 

 

Spoiler for
Hint : The 3 weighing solution is very easy..
 

Spoiler for no uncertainty 2 weighing

Spoiler for


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