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For younger learners

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Perimeter Puzzle

Age 11 to 14
ShortChallenge Level Yellow starYellow star
Secondary curriculum
  • Problem
  • Solutions



44cm                 46cm             52cm      

58cm                           62cm      



74cm                76cm    



You can find more short problems, arranged by curriculum topic, in our short problems collection.

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Hallway Borders

What are the possible dimensions of a rectangular hallway if the number of tiles around the perimeter is exactly half the total number of tiles?

Square Pegs

Which is a better fit, a square peg in a round hole or a round peg in a square hole?

Boxed In

A box has faces with areas 3, 12 and 25 square centimetres. What is the volume of the box?

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The NRICH Project aims to enrich the mathematical experiences of all learners. To support this aim, members of the NRICH team work in a wide range of capacities, including providing professional development for teachers wishing to embed rich mathematical tasks into everyday classroom practice.

NRICH is part of the family of activities in the Millennium Mathematics Project.

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