Pythagoras' theorem

  • The Dodecahedron
    problem

    The dodecahedron

    Age
    16 to 18
    Challenge level
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    What are the shortest distances between the centres of opposite faces of a regular solid dodecahedron on the surface and through the middle of the dodecahedron?
  • Corridors
    problem

    Corridors

    Age
    14 to 16
    Challenge level
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    A 10x10x10 cube is made from 27 2x2 cubes with corridors between them. Find the shortest route from one corner to the opposite corner.
  • Semi-detached
    problem

    Semi-detached

    Age
    14 to 16
    Challenge level
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    A square of area 40 square cms is inscribed in a semicircle. Find the area of the square that could be inscribed in a circle of the same radius.
  • Circumnavigation
    problem

    Circumnavigation

    Age
    14 to 16
    Challenge level
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    The sides of a triangle are 25, 39 and 40 units of length. Find the diameter of the circumscribed circle.
  • In a Spin
    problem

    In a spin

    Age
    14 to 16
    Challenge level
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    What is the volume of the solid formed by rotating this right angled triangle about the hypotenuse?
  • Cutting a Cube
    problem

    Cutting a cube

    Age
    11 to 14
    Challenge level
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    A half-cube is cut into two pieces by a plane through the long diagonal and at right angles to it. Can you draw a net of these pieces? Are they identical?
  • Take a square
    problem

    Take a square

    Age
    14 to 16
    Challenge level
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    Cut off three right angled isosceles triangles to produce a pentagon. With two lines, cut the pentagon into three parts which can be rearranged into another square.
  • Semi-Square
    problem

    Semi-square

    Age
    14 to 16
    Challenge level
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    What is the ratio of the area of a square inscribed in a semicircle to the area of the square inscribed in the entire circle?
  • Crescents and triangles
    problem

    Crescents and triangles

    Age
    14 to 16
    Challenge level
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    Can you find a relationship between the area of the crescents and the area of the triangle?