It's time for a mind boggling puzzle.Analyze the statements below and find out who did it.

Please note that three of the statements below are false.

1. Mr. Reese: 'Mr. Bilbo did it.'
2. Mr. Bilbo: 'Mr. Reese did it.'
3. Mr. Gerry: 'Mr. Bilbo’s telling the truth.'
4. Mr. Yang: 'Mr. Gerry’s not lying.'

Mr. Bilbo did it.

Let us consider all the statements one by one for every person and find out.

Case 1: Mr. Bilbo did it, then
Statement 1 => true
Statement 2 => false (as Reese did not do it)
Statement 3 => false (as Mr. Bilbo is lying)
Statement 4 => false (as Mr. Gerry is lying)
It was Mr. Bilbo who did it. But let us confirm by taking up other cases as well.

Case 2: Mr. Reese did it, then
Statement 1 => false (as Mr. Bilbo did not do it)
Statement 2 => true
Statement 3 => true (as Mr. Bilbo is not lying)
Two statements are true whereas only one should be true, thus Mr. Reese did not do it.

Case 3: Mr. Gerry did it, then
Statement 1 => false (as Mr. Bilbo did not do it)
Statement 2 => false (as Mr. Reese did not do it)
Statement 3 => false (as Mr. Bilbo is lying)
Statement 4 => false (as Mr. Gerry is lying)
All four statements stand false, thus Mr. Gerry did not do it.

Case 4: Mr. Yang did it, then
Statement 1 => false (as Mr. Bilbo did not do it)
Statement 2 => false (as Mr. Reese did not do it)
Statement 3 => false (as Mr. Bilbo is lying)
Statement 4 => false (as Mr. Gerry is lying)

All four statements are false therefore Mr. Yang did not do it.

We have verified with everyone and now know that it was Mr. Bilbo who did it.

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