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Ninety nine coins plus one catch (Posted on 2014-06-01) Difficulty: 3 of 5
You are given a task of locating one faulty coin out of 99 identical in appearance coins i.e. 98 of equal weight and one of a lesser weight; and to achieve it within seven weighings, using a balance scale.

Sounds familiar and easy (37>99)?

Familiar? Yes.

Easy? Not quite!

How can you accomplish it if no coin may be weighed more than twice ?

Bonus task: After devising the requested procedure please generalize:
How many coins (n-1 normal and one lighter) can be resolved within k weighings?

No Solution Yet Submitted by Ady TZIDON    
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Hints/Tips E R R O R : ninety six is the correct number | Comment 1 of 7

Should be  

 97  identical in appearance coins i.e. 96 of equal weight and one of a lesser weight;

Then it is fully solvable (worst choice included).


If anyone can correct the puzzle  - please do so ASAP.



Edited on July 2, 2014, 2:37 am
  Posted by Ady TZIDON on 2014-06-01 16:03:33

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