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For younger learners

  • Early Years Foundation Stage

Pentagon Ring

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

Equal regular pentagons are placed together to form a ring.  
The diagram shows the first three pentagons.

How many pentagons are needed to complete the ring?

circle with chain of 3 pentagons.

 

If you liked this problem, here is an NRICH task which challenges you to use similar mathematical ideas.

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

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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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