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

Home > Logic
All Wrong at the Olympic Games (Posted on 2007-06-15) Difficulty: 3 of 5
In the marathon, all the competing countries were from Africa, but not the usual runners, and maybe that caused all prognostics on the race results to be wrong:

1) Algeria will not win the gold, nor Botswana the silver.
2) Chad will win a medal, and Djibouti will not.
3) Djibouti and Egypt will both win medals.
4) Djibouti will not win the silver, nor Egypt the bronze.
5) Algeria will win a medal, and Chad will not.

Who won which of the medals?

See The Solution Submitted by Federico Kereki    
Rating: 4.2500 (4 votes)

Comments: ( Back to comment list | You must be logged in to post comments.)
Solution Comment 14 of 14 |

Since the prognostics are wrong the inverse statements are:

1.  A will not win gold (OR) B will not win Silver

2.  C will win no medal (AND) D will win a medal

3.  Both D&E together will not win medals

4.  D will win Silver (OR) E will win Bronze

5.  Both A&C together will not not win medals

So 2 takes out C and puts in D

That means that 3 forces E out

That means in 4 With E out that makes D win Silver

5 eliminates the already eliminated C and allows A to remain in medal contention

So 1 allows A to win a non Gold (silver is already taken by D in 4) so A wins Bronze

Also 1 allows B to win a non-Silver, non-Bronze (Silver is already taken by D in 4 and Bronze is taken by A in the first half of 1), so B takes the Gold

                 Gold             Silver              Bronze

A                  ?                   ?                     win - deduced

B            win-deduced      ?                     ?

C                can't win       can't win          can't win

D                can't win       must win          can't win

E                can't win       can't win          can't win


  Posted by Jim on 2007-12-21 17:42:59
Please log in:
Login:
Password:
Remember me:
Sign up! | Forgot password


Search:
Search body:
Forums (0)
Newest Problems
Random Problem
FAQ | About This Site
Site Statistics
New Comments (3)
Unsolved Problems
Top Rated Problems
This month's top
Most Commented On

Chatterbox:
Copyright © 2002 - 2024 by Animus Pactum Consulting. All rights reserved. Privacy Information