All about flooble | fun stuff | Get a free chatterbox | Free JavaScript | Avatars    
perplexus dot info

Home > Logic > Weights and Scales
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    
No Rating

Comments: ( You must be logged in to post comments.)
  Subject Author Date
SolutionCorrection! (and bonus task)tomarken2014-07-02 14:56:37
SolutionSolution, explainedtomarken2014-07-02 12:57:46
re(3): Any thoughts on this one? small hint - open to allAdy TZIDON2014-07-02 12:30:59
re(2): Any thoughts on this one?tomarken2014-07-02 09:46:41
Hints/Tipsre: Any thoughts on this one?Ady TZIDON2014-07-02 02:46:21
QuestionAny thoughts on this one?tomarken2014-06-30 16:50:58
Hints/TipsE R R O R : ninety six is the correct numberAdy TZIDON2014-06-01 16:03:33
Please log in:
Remember me:
Sign up! | Forgot password

Search body:
Forums (0)
Newest Problems
Random Problem
FAQ | About This Site
Site Statistics
New Comments (4)
Unsolved Problems
Top Rated Problems
This month's top
Most Commented On

Copyright © 2002 - 2021 by Animus Pactum Consulting. All rights reserved. Privacy Information