Being resilient

  • Expenses
    problem
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    Expenses

    Age
    14 to 16
    Challenge level
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    What is the largest number which, when divided into these five numbers in turn, leaves the same remainder each time?

  • Fair Shares?
    problem
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    Fair Shares?

    Age
    14 to 16
    Challenge level
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    A mother wants to share some money by giving each child in turn a lump sum plus a fraction of the remainder. How can she do this to share the money out equally?

  • Why 24?
    problem
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    Why 24?

    Age
    14 to 16
    Challenge level
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    Take any prime number greater than 3 , square it and subtract one. Working on the building blocks will help you to explain what is special about your results.

  • In a box
    problem
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    In a Box

    Age
    14 to 16
    Challenge level
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    Chris and Jo put two red and four blue ribbons in a box. They each pick a ribbon from the box without looking. Jo wins if the two ribbons are the same colour. Is the game fair?

  • Inscribed in a Circle
    problem
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    Inscribed in a Circle

    Age
    14 to 16
    Challenge level
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    The area of a square inscribed in a circle with a unit radius is 2. What is the area of these other regular polygons inscribed in a circle with a unit radius?

  • Perfectly Square
    problem
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    Perfectly Square

    Age
    14 to 16
    Challenge level
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    The sums of the squares of three related numbers is also a perfect square - can you explain why?

  • The Spider and the Fly
    problem
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    The Spider and the Fly

    Age
    14 to 16
    Challenge level
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    A spider is sitting in the middle of one of the smallest walls in a room and a fly is resting beside the window. What is the shortest distance the spider would have to crawl to catch the fly?

  • Areas of parallelograms
    problem
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    Areas of Parallelograms

    Age
    14 to 16
    Challenge level
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    Can you find the area of a parallelogram defined by two vectors?

  • Speeding boats
    problem
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    Speeding Boats

    Age
    14 to 16
    Challenge level
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    Two boats travel up and down a lake. Can you picture where they will cross if you know how fast each boat is travelling?

  • Partly Painted Cube
    problem
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    Partly Painted Cube

    Age
    14 to 16
    Challenge level
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    Jo made a cube from some smaller cubes, painted some of the faces of the large cube, and then took it apart again. 45 small cubes had no paint on them at all. How many small cubes did Jo use?