Conjecturing and generalising

  • problem
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    Cyclic Quadrilaterals

    Age
    11 to 16
    Challenge level
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    Draw some quadrilaterals on a 9-point circle and work out the angles. Is there a theorem?

  • Charlie's delightful machine
    problem
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    Charlie's Delightful Machine

    Age
    11 to 16
    Challenge level
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    Here is a machine with four coloured lights. Can you develop a strategy to work out the rules controlling each light?

  • Multiple Surprises
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    Multiple Surprises

    Age
    11 to 16
    Challenge level
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    Sequences of multiples keep cropping up...

  • Parallelogram It
    problem
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    Parallelogram It

    Age
    11 to 16
    Challenge level
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    Players take it in turns to choose a dot on the grid. The winner is the first to have four dots that can be joined to form a parallelogram.

  • Robotic Rotations
    problem
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    Robotic Rotations

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

  • Take Three From Five
    problem
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    Take Three from Five

    Age
    11 to 16
    Challenge level
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    Caroline and James pick sets of five numbers. Charlie tries to find three that add together to make a multiple of three. Can they stop him?

  • Tourism
    problem
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    Tourism

    Age
    11 to 16
    Challenge level
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    If you can copy a network without lifting your pen off the paper and without drawing any line twice, then it is traversable. Decide which of these diagrams are traversable.

  • More Twisting and Turning
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    More Twisting and Turning

    Age
    11 to 16
    Challenge level
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    It would be nice to have a strategy for disentangling any tangled ropes...

  • Searching for mean(ing)
    problem
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    Searching for Mean(ing)

    Age
    11 to 16
    Challenge level
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    If you have a large supply of 3kg and 8kg weights, how many of each would you need for the average (mean) of the weights to be 6kg?