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Flag-tastic

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

A picture of a flag is to be completed by shading two squares that do not share an edge. The diagram shows one way in which this can be done.

Flag

How many different possible completed pictures are there (including the one shown)?

 

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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Counting on Letters

The letters of the word ABACUS have been arranged in the shape of a triangle. How many different ways can you find to read the word ABACUS from this triangular pattern?

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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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