Explaining, convincing and proving

  • Six Ten Total
    problem
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    Six Ten Total

    Age
    7 to 11
    Challenge level
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    This challenge combines addition, multiplication, perseverance and even proof.

  • Six Numbered Cubes
    problem
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    Six Numbered Cubes

    Age
    7 to 11
    Challenge level
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    This task combines spatial awareness with addition and multiplication.

  • Curious number
    problem
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    Curious Number

    Age
    7 to 11
    Challenge level
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    Can you order the digits from 1-3 to make a number which is divisible by 3 so when the last digit is removed it becomes a 2-figure number divisible by 2, and so on?

  • Square subtraction
    problem
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    Square Subtraction

    Age
    7 to 11
    Challenge level
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    Look at what happens when you take a number, square it and subtract your answer. What kind of number do you get? Can you prove it?

  • Subtraction Surprise
    problem
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    Subtraction Surprise

    Age
    7 to 14
    Challenge level
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    Try out these calculations. Are you surprised by the results?

  • Got It
    problem
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    Got It

    Age
    7 to 14
    Challenge level
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    A game for two people, or play online. Given a target number, say 23, and a range of numbers to choose from, say 1-4, players take it in turns to add to the running total to hit their target.

  • Your number is...
    problem
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    Your Number Is...

    Age
    7 to 14
    Challenge level
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    Think of a number and follow the machine's instructions... I know what your number is! Can you explain how I know?

  • A rolled up old-fashioned treasure map.
    problem
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    Treasure Hunt

    Age
    7 to 14
    Challenge level
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    Can you find a reliable strategy for choosing coordinates that will locate the treasure in the minimum number of guesses?

  • missing multipliers
    problem
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    Missing Multipliers

    Age
    7 to 14
    Challenge level
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    What is the smallest number of answers you need to reveal in order to work out the missing headers?

  • The Number Jumbler
    problem
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    The Number Jumbler

    Age
    7 to 14
    Challenge level
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    The Number Jumbler can always work out your chosen symbol. Can you work out how?