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

Home > Logic > Liars and Knights
Legally Blonde (Posted on 2016-12-19) Difficulty: 1 of 5
You meet three blonde women, A, B, and C. Each of them is either a knight or a liar. Exactly one of them is Elle Woods.

A:I am Elle Woods.
B:I am Elle Woods.
C:At least two of us are liars.

What are A, B, and C, and who is Elle Woods?

No Solution Yet Submitted by Math Man    
Rating: 3.0000 (1 votes)

Comments: ( Back to comment list | You must be logged in to post comments.)
Solution re: Logical Outcome (Spoiler) | Comment 2 of 8 |
(In reply to Logical Outcome (Spoiler) by Ady TZIDON)

I agree with Ady's answer, but not his logic.  You cannot determine that A and B are false without looking at statement C.  It is possible that A is true and B is false, or vice versa.

----------------------------------------------------------
Correct Logic:

If C is a liar then there is at most one liar, so A and B are both telling the truth.  But this is a contradiction, so C is telling the truth.  Then there are at least two liars, and they must be A and B, so A and B are not Elle Woods, so C must be Elle Woods.

  Posted by Steve Herman on 2016-12-19 09:50:25
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 (5)
Unsolved Problems
Top Rated Problems
This month's top
Most Commented On

Chatterbox:
Copyright © 2002 - 2017 by Animus Pactum Consulting. All rights reserved. Privacy Information