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Who stole the candy bar? (Posted on 2005-02-03) Difficulty: 3 of 5

During lunch hour at school, a group of five boys from Miss Jones' home room visited a nearby lunch wagon. One of the five boys took a candy bar without paying for it. When the boys were questioned by the school principal, they made the following statements in respective order:

1. Rex: "Neither Earl nor I did it."

2. Jack: "It was Rex or Abe."

3. Abe: "Both Rex and Jack are liars."

4. Dan: "Abe's statement is not true; one of them is lying and the other is speaking the truth."

5. Earl: "What Dan said is wrong."

When Miss Jones was consulted, she said, "Three of these boys are knights, but two are liars." Assuming that Miss Jones is correct, can you determine who took the candy bar?

See The Solution Submitted by Jane Doe    
Rating: 3.0000 (5 votes)

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Solution solution | Comment 23 of 38 |
Thief = Abe

Liars = Abe and Dan

It's easiest if you separate it into 2 different riddles; who are the liars and who stole the candy bars. If you look only at the statements pertaining to who is lying, it is relatively easy to figure out who the liars are. If Abe's statement were true, that would make 3 liars (Rex, Jack and Dan). If Dan's statement were true, that would also make 3 liars (Abe, Rex or Jack, and Earl). Earl's statement is the only one that can be true in that category. Having figured out that Dan and Abe are both liars, that makes Jack and Rex's statements true by default. After that if you look at the statements pertaining to the actual theft, it is a rather simple deduction. Rex didn't do it, Earl didn't do it, therefore Jack's statement correctly fingers the thief; Abe took the candybar.

  Posted by KP on 2006-01-25 01:30:35
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