Brain Teasers
Who Robbed the Bank?
The angry chief of police did roar,
"Who robbed the bank out of you four?"
When Al was asked, he said right then,
"The thief was Ben! The thief was Ben!"
Ben said to the policin' man,
"The thief was Dan! The thief was Dan!"
When Carl was questioned, he exclaimed,
"I'm not the one who should be blamed!"
When Dan was questioned, he replied,
"When Ben said it was me, he lied!"
If three of four suspects speak true,
And one speaks false, then who oh who?
And what if only one was frank?
But most of all, who robbed the bank?
"Who robbed the bank out of you four?"
When Al was asked, he said right then,
"The thief was Ben! The thief was Ben!"
Ben said to the policin' man,
"The thief was Dan! The thief was Dan!"
When Carl was questioned, he exclaimed,
"I'm not the one who should be blamed!"
When Dan was questioned, he replied,
"When Ben said it was me, he lied!"
If three of four suspects speak true,
And one speaks false, then who oh who?
And what if only one was frank?
But most of all, who robbed the bank?
Answer
If only one is lying, Ben robbed the bank.If only one is telling the truth, Carl robbed the bank.
Since Dan's statement was that Ben was lying, exactly one of these two must be telling the truth and the other must be lying. If Ben is telling the truth and Dan is lying, Dan must be the thief, which means that Al is lying and Carl is telling the truth. But now we have two truthtellers and two liars. So this cannot be right.
Therefore, if there is only one liar, it must be Ben. Al can only be telling the truth if Ben was the robber. If there is only one truthteller, it must be Dan. Carl can only be lying if Carl was the robber.
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Comments
Love the way this logic problem was presented in verse!
So far, two of my teasers have become "daily teasers". This could be my third one!
I love the verse, very clean. I also enjoyed the dual interpretation, making two puzzles out of one. Quite novel. It was an easy logic puzzle, so great for those who don't typically enjoy the deep thinking. Very accessible to all. Terrific.
Be sure to check out all my other delightful teasers!!!
I am not going to compliment you as you have done enough of that yourself. Sad!
Right on Babe
Fun, enjoyable but confusing teaser. I got that Ben was the thief but did not realize you had to work it a second way also to get Carl as the answer. The first time I have ever encountered a teaser like this. Personally I prefer the single answer logic teasers.
Am afraid I'm with: MrBill51 on this, you should have made it quite clear that 2 answers were required?
So I wouldn't be blowing my own trumpet too loudly if I were you!
So I wouldn't be blowing my own trumpet too loudly if I were you!
A scip model for solving this teaser can be found at
https://gist.github.com/saska-gist/
69606c9485aefae0177025061e38abd8
https://gist.github.com/saska-gist/
69606c9485aefae0177025061e38abd8
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