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For younger learners

  • Early Years Foundation Stage

Natural Sum

Age 14 to 16
Challenge Level Yellow star
  • Problem
  • Teachers' Resources

Possible support
Try the problems
More Sequences and Series,
and OK Now Prove It

Possible extension
Picture Story,
Telescoping Series
and Seriesly
Read the article Proof by Induction.

You may also like

Series Sums

Let S1 = 1 , S2 = 2 + 3, S3 = 4 + 5 + 6 ,........ Calculate S17.

Mystic Rose

Use the animation to help you work out how many lines are needed to draw mystic roses of different sizes.

Slick Summing

Watch the video to see how Charlie works out the sum. Can you adapt his method?

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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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