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Counting Counters

Age 7 to 11
Challenge Level Yellow starYellow star
  • Problem
  • Student Solutions
  • Teachers' Resources



Take a counter and surround it by a ring of other counters that MUST touch two others. How many counters do you need to do this?
 
Imagine surrounding this ring with more counters.
How many more counters are needed now?
How many counters will there be altogether?

Were you right?

What about a bigger ring? And another? And another? 

How many counters will there be in the $9$th ring?
How many do you think there will be in the $100$th ring?
How would you predict how many counters there will be in any ring?
 

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Tangrams

Can you make five differently sized squares from the interactive tangram pieces?

Polydron

This activity investigates how you might make squares and pentominoes from Polydron.

Construct-o-straws

Make a cube out of straws and have a go at this practical challenge.

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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.

Links to the University of Cambridge website University of Cambridge logo Links to the NRICH website Home page NRICH logo