Brainteaser #30 – The Shoplifters

It’s lunch break at school and 5 unruly students head to the shop.

One of them steals a jumbo pack of Monster Munch (Flamin’ Hot, of course).

The shop keeper notices the little blighters make off with the Monster Munch and catches them up.

He takes them into school for a meeting with their teacher, Mr Bolton.

When questioned, the boys say:

Jimmy: “It was Pritch or Davey!”

Pritch: “It wasn’t me, or Ed.”

Davey: “You’re both liars!”

Donny: “Only one of them is lying (Jimmy or Pritch), the other is telling the truth.”

Ed: “No Donny, that isn’t true…”

Mr Bolton says that 3 of the students tell the truth, the others 2 always lie.

How can you work out who stole the Monster Munch?

Show Answer

You can deduce the answer by considering:

  • Donny and Ed contradict each other, so only one of them can be telling the truth – the other is a liar
  • That leaves one other liar
  • Since Davey said both Jimmy and Pritch were lying, he must be lying as there is only one liar left, not two
  • This makes Davey the second liar
  • Jimmy and Pritch are therefore telling the truth
  • This means Davey stole the Monster Munch