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Unexpected Ordering

Age 5 to 7
Challenge Level Yellow star
  • Problem
  • Getting Started
  • Student Solutions
  • Teachers' Resources

Watch the video below:


If you can't access YouTube, here is a direct link to the video: UnexpectedOrdering.mp4. You can view closed captions by selecting 'CC' in the bottom menu of the video once it is playing.

What do you notice?
What do you want to ask?

Watch it again.

Perhaps some of your questions have been answered.  Or you might have thought of new questions.

Try the task for yourself.  What happens?
What happens if you use a different order of 1s and 2s in dealing out the cards? 

Can you explain why this is maths and not a magic trick?

You may be interested in the other problems in our Using Wonder to Promote Curiosity Feature.

This problem featured in an NRICH video in June 2020.

Related Collections

  • Other videos
  • Back to LTHC resources

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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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