Reasoning, convincing and proving

  • Yih or Luk tsut k'i or Three Men's Morris
    game

    Yih or Luk tsut k'i or Three Men's Morris

    Age
    11 to 18
    Challenge level
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    Some puzzles requiring no knowledge of knot theory, just a careful inspection of the patterns. A glimpse of the classification of knots and a little about prime knots, crossing numbers and knot arithmetic.

  • Anti-Magic Square
    problem

    Anti-magic square

    Age
    11 to 14
    Challenge level
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    You may have met Magic Squares, now meet an Anti-Magic Square. Its properties are slightly different - can you still solve it?
  • Exponential intersection
    problem

    Exponential intersection

    Age
    16 to 18
    Challenge level
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    Can the pdfs and cdfs of an exponential distribution intersect?
  • Next-door Numbers
    problem

    Next-door numbers

    Age
    5 to 7
    Challenge level
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    Florence, Ethan and Alma have each added together two 'next-door' numbers. What is the same about their answers?
  • Angles inside
    problem

    Angles inside

    Age
    11 to 14
    Challenge level
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    Draw some angles inside a rectangle. What do you notice? Can you prove it?

  • Number Lines in Disguise
    problem

    Number lines in disguise

    Age
    7 to 14
    Challenge level
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    Some of the numbers have fallen off Becky's number line. Can you figure out what they were?

  • More Number Sandwiches
    problem

    More number sandwiches

    Age
    11 to 16
    Challenge level
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    When is it impossible to make number sandwiches?
  • Robotic Rotations
    problem

    Robotic rotations

    Age
    11 to 16
    Challenge level
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    How did the the rotation robot make these patterns?

  • Statement Snap
    problem

    Statement snap

    Age
    7 to 14
    Challenge level
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    You'll need to know your number properties to win a game of Statement Snap...

  • Making Pathways
    problem

    Making pathways

    Age
    7 to 11
    Challenge level
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    Can you find different ways of creating paths using these paving slabs?