Jump to content

Welcome to BrainDen.com - Brain Teasers Forum

Welcome to BrainDen.com - Brain Teasers Forum. Like most online communities you must register to post in our community, but don't worry this is a simple free process. To be a part of BrainDen Forums you may create a new account or sign in if you already have an account.
As a member you could start new topics, reply to others, subscribe to topics/forums to get automatic updates, get your own profile and make new friends.

Of course, you can also enjoy our collection of amazing optical illusions and cool math games.

If you like our site, you may support us by simply clicking Google "+1" or Facebook "Like" buttons at the top.
If you have a website, we would appreciate a little link to BrainDen.

Thanks and enjoy the Den :-)
Guest Message by DevFuse

- - - - -

Troll Problem

  • Please log in to reply
3 replies to this topic

#1 nam517



  • Members
  • Pip
  • 1 posts

Posted 11 September 2007 - 06:40 AM

Can anyone help me solve this puzzle?
If you can that would be great.
Thank You

You are walking in a forest and come to a fork in the road. There is a troll standing there. You can either go right or left. One way leads you out of the forest safely and the other way leads you to a very painful death by wild animals. You can ask the troll one question only. Now, here's the tricky part.... The troll tells the truth every other day. For example, if the troll tells the truth today, he will lie tomorrow. If he lies today, he will tell the trut tomorrow. You don't know which day he's on (i.e. truth day or lie day). You have one and only question to save your life. What will ask the troll?
  • 0

#2 bonanova



  • Moderator
  • PipPipPipPip
  • 6161 posts
  • Gender:Male
  • Location:New York

Posted 11 September 2007 - 07:02 AM

We assume the troll knows which road is safe.

Ask: "Which road would you have told me yesterday was safe?"

He'll either lie about telling you the truth or tell the truth about lying to you.
Either way, he'll point to the dangerous road.

Then take the other road.
  • 0

Vidi vici veni.

#3 rookie1ja


    Senior Member

  • Site Admin
  • PipPipPipPip
  • 1344 posts
  • Gender:Male
  • Location:Slovakia

Posted 11 September 2007 - 01:18 PM

I have one puzzle with the same principle ... check Honestants and Swindlecants III.
  • 0

rookie1ja (site admin)
Optical Illusions
Support BrainDen

"To start: Press any key... Where's the 'any' key?" - Homer Simpson

#4 unreality


    Senior Member

  • Members
  • PipPipPipPip
  • 6375 posts

Posted 11 September 2007 - 08:18 PM

Most Liar/Truthteller riddles with two (or three) directions/doors/paths/etc to go are based on this princriple, ie, asking one man what the other would say (in this case, the "other" man is the liar or truthteller of yesterday because he was different yesterday)
  • 0

0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users