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Sissa's Reward

Age 11 to 14
Challenge Level Yellow starYellow star
  • Problem
  • Getting Started
  • Student Solutions
Try making a table with the number of the square and the number of grains of rice on that square, this way it may be easier to spot a pattern. For example:
Square Number of grains of rice
1 1
2
2
3 4
4 ?
5 ?
6 ?
Try to link the number in the left column to its related number in the right column. Can you think of a general rule?
You may need to use powers.

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Subtraction Surprise

Try out some calculations. Are you surprised by the results?

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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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