Being resilient

  • Flippin' discs
    problem
    Favourite

    Flippin' Discs

    Age
    11 to 14
    Challenge level
    1 out of 3

    Discs are flipped in the air. You win if all the faces show the same colour. What is the probability of winning?

  • Odds and Evens
    problem
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    Odds and Evens

    Age
    11 to 14
    Challenge level
    1 out of 3

    Are these games fair? How can you tell?

  • Substitution Cipher
    problem
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    Substitution Cipher

    Age
    11 to 14
    Challenge level
    1 out of 3

    Find the frequency distribution for ordinary English, and use it to help you crack the code.

  • m, m and m
    problem
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    M, M and M

    Age
    11 to 14
    Challenge level
    1 out of 3

    If you are given the mean, median and mode of five positive whole numbers, can you find the numbers?

  • Elevenses
    problem
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    Elevenses

    Age
    11 to 14
    Challenge level
    1 out of 3

    How many pairs of numbers can you find that add up to a multiple of 11? Do you notice anything interesting about your results?

  • Keep it simple
    problem
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    Keep It Simple

    Age
    11 to 14
    Challenge level
    1 out of 3

    Can all unit fractions be written as the sum of two unit fractions?

  • How steep is the slope?
    problem
    Favourite

    How Steep Is the Slope?

    Age
    11 to 14
    Challenge level
    1 out of 3

    On the grid provided, we can draw lines with different gradients. How many different gradients can you find? Can you arrange them in order of steepness?

  • How much can we spend?
    problem
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    How Much Can We Spend?

    Age
    11 to 14
    Challenge level
    1 out of 3

    A country has decided to have just two different coins. Which totals can be made? Is there a largest total that cannot be made? How do you know?

  • Place your orders
    problem
    Favourite

    Place Your Orders

    Age
    11 to 14
    Challenge level
    1 out of 3

    Can you rank these sets of quantities in order, from smallest to largest? Can you provide convincing evidence for your rankings?

  • Can you Make 100?
    problem
    Favourite

    Can You Make 100?

    Age
    11 to 14
    Challenge level
    1 out of 3

    How many ways can you find to put in operation signs (+, −, ×, ÷) to make 100?