Being resilient

  • Litov's Mean Value Theorem
    problem
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    Litov's Mean Value Theorem

    Age
    11 to 14
    Challenge level
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    Start with two numbers and generate a sequence where the next number is the mean of the last two numbers...

  • Charlie's delightful machine
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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...

  • Same length
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    Same Length

    Age
    11 to 16
    Challenge level
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    Construct two equilateral triangles on a straight line. There are two lengths that look the same - can you prove it?

  • Funny Factorisation
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    Funny Factorisation

    Age
    11 to 16
    Challenge level
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    Using the digits 1 to 9, the number 4396 can be written as the product of two numbers. Can you find the factors?

  • Take Three From Five
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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?

  • Product Sudoku
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    Product Sudoku

    Age
    11 to 16
    Challenge level
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    The clues for this Sudoku are the product of the numbers in adjacent squares.

  • 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...

  • Wipeout
    problem
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    Wipeout

    Age
    11 to 16
    Challenge level
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    Can you do a little mathematical detective work to figure out which number has been wiped out?