Difficulty: Tricky

A new class of aliens is due to start at Alien Academy. The teachers need to know the age of each alien, but can’t contact them. Luckily, they have a few clues to help them.

  • There are five aliens (Filp, Agg, Nim, Phod, and Mex) and each alien is a different age (7, 9, 10, 12, 14).
  • Filp is double the age of one of the other aliens.
  • Mex’s age is an odd number.
  • Agg is five years younger than Phod.

Can you help the teachers work out each alien’s age?

Scroll down or click for a hint, or the answer!


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Brainteaser hint

Remember that every alien gets one age, and also each age can only be given to one alien.

Try writing lists of names and ages and mark the ones you’ve already worked out – that will make it easier to see what you have left to work with.

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Brainteaser answer

Filp is double the age of one of the other aliens, so must be 14 (double 7).

Mex’s age is an odd number, so could be 7 or 9.

Agg is five years younger than Phod, so Phod must be five years older than Agg. We know Phod can’t be 14, because that’s Filp’s age. So Phod must be 12, and Agg must be 7.

We only have one odd age left, so we know Mex is 9.

The only alien left is Nim, who must be 10.

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