A group of campers have been on vacation so long, that they've forgotten the day of the week. The following conversation ensues.

Darryl: What's the day? I don't think it is Thursday, Friday or Saturday.

Tracy: Well that doesn't narrow it down much. Yesterday was Sunday.

Melissa: Yesterday wasn't Sunday, tomorrow is Sunday.

Ben: The day after tomorrow is Saturday.

Adrienne: The day before yesterday was Thursday.

Susie: Tomorrow is Saturday.

David: I know that the day after tomorrow is not Friday.

If only one person's statement is true, what day of the week is it?

(In reply to Solution by e.g.)

I have an issue with the problem wording.  Read below.

There is only one truth teller.  It cannot be Tracy, Melissa, Ben, Adrienne, or Susie, because they would agree with David. 

No one of Ben, Susie, or Adrienne's statements have to be true if Darryl's is false, because he's stating an opinion about what he thinks - not about whether the day is or isn't one of those days.

Truth teller is either David or Darryl.

If Darryl's statement is true, then David's is false, which makes it Wednesday.

If David's statement is true, then it's not Wednesday.  Also, it's not Sunday (Melissa), Monday (Tracy), Thursday (Ben), Friday (Susie), Saturday (Adrienne).  Therefore it's Tuesday.

Therefore, it's either Tuesday or Wednesday, and not enough information was provided.

Posted by Ryan on 2004-04-08 14:47:12