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  • Early Years Foundation Stage

Perimeter Puzzle

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



If you join four copies of the triangle shown, without gaps or overlaps, how many different parallelograms can you make? 

What are the perimeters of the different parallelograms?





This problem has been adapted from the UKMT Mathematical Challenges.
You can find more short problems, arranged by curriculum topic, in our short problems collection.

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

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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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