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For younger learners

  • Early Years Foundation Stage

Intersection Sudoku 1

Age 11 to 16
Challenge Level Yellow starYellow star
  • Problem
  • Getting Started
  • Student Solutions

  • A clue like 2567 in cell (8,2) confirms the positions of four of the numbers in the surrounding 3x3 square.

  • It is useful to remember that the same number cannot appear in the same row or in the same 3x3 square. This can help with a clue such as1223 in cell (8,6) because it tells you the position of one of the twos.



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Consecutive Numbers

An investigation involving adding and subtracting sets of consecutive numbers. Lots to find out, lots to explore.

Tea Cups

Place the 16 different combinations of cup/saucer in this 4 by 4 arrangement so that no row or column contains more than one cup or saucer of the same colour.

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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