Reply
Mon 8 Mar, 2010 09:05 pm
So my professor gave us this riddle as extra credit, but i cant seem to figure it out. any suggestions? here it is:
On a certain island, the inhabitants are divided into 2 groups, those who always lie, and those who always tell the ruth. One day, a visitor stops 3 inhabitants to ask for directions.
"All 3 of us are liars," warns the first one.
"Not so! Only one of us is a liar," says the second.
"Not so," says the third, "the other two are the lying."
Which if any of the 3 islanders can the visitor trust for the correct directions?
Let me know if you all come up with something!
Thanks!!
Number 3 is telling the truth.
If No 1 is telling the truth then it cant be that all three are liars, because that means No 1 is not lying. Therefor No 1 is a liar.
If No 2 is telling the truth, the liar has already been established as No 1. Therefore No 3 is telling the truth. But No 2 cant be telling the truth, because No 3 says the other two are liars, not just No 1. Therefore No 2 is lying also.
If No 3 is telling the truth, then the other two are liars. If No 3 is lying, then one or the other of the first two might be telling the truth. This has been established as incorrect. Therefore, the only option left is that No 3 is telling the truth and can give truthful directions.
@Ionus,
wow! that sounds really good...thanks!!
@ladeelaenne,
Don't trust him, he's lying.
@ladeelaenne,
Dont you believe Seed, ladadaeeelaenenene..however you pronounce it....he is a notorious liar and he has tatoos ! Yes, I am afraid its true !
Stumble It!
Tweet This
Bookmark on Delicious
Share on Facebook
Share on MySpace