Polyhedra

  • Redblue
    problem

    Redblue

    Age
    7 to 11
    Challenge level
    filled star filled star filled star
    Investigate the number of paths you can take from one vertex to another in these 3D shapes. Is it possible to take an odd number and an even number of paths to the same vertex?
  • Which solid?
    problem

    Which solid?

    Age
    7 to 16
    Challenge level
    filled star empty star empty star
    This task develops spatial reasoning skills. By framing and asking questions a member of the team has to find out what mathematical object they have chosen.
  • Icosian Game
    problem

    Icosian game

    Age
    11 to 14
    Challenge level
    filled star empty star empty star

    This problem is about investigating whether it is possible to start at one vertex of a platonic solid and visit every other vertex once only returning to the vertex you started at.

  • Triangles to Tetrahedra
    problem

    Triangles to tetrahedra

    Age
    11 to 14
    Challenge level
    filled star filled star filled star

    Imagine you have an unlimited number of four types of triangle. How many different tetrahedra can you make?

  • Which solids can we make?
    problem

    Which solids can we make?

    Age
    11 to 14
    Challenge level
    filled star filled star filled star

    Interior angles can help us to work out which polygons will tessellate. Can we use similar ideas to predict which polygons combine to create semi-regular solids?

  • Dodecawhat
    problem

    Dodecawhat

    Age
    14 to 16
    Challenge level
    filled star empty star empty star

    Follow instructions to fold sheets of A4 paper into pentagons and assemble them to form a dodecahedron. Calculate the error in the angle of the not perfectly regular pentagons you make.

  • Proximity
    problem

    Proximity

    Age
    14 to 16
    Challenge level
    filled star filled star empty star

    We are given a regular icosahedron having three red vertices. Show that it has a vertex that has at least two red neighbours.

  • Three cubes
    problem

    Three cubes

    Age
    14 to 16
    Challenge level
    filled star filled star empty star

    Can you work out the dimensions of the three cubes?

  • Tetrahedra Tester
    problem

    Tetrahedra tester

    Age
    14 to 16
    Challenge level
    filled star filled star empty star

    An irregular tetrahedron is composed of four different triangles. Can such a tetrahedron be constructed where the side lengths are 4, 5, 6, 7, 8 and 9 units of length?

  • Platonic Planet
    problem

    Platonic planet

    Age
    14 to 16
    Challenge level
    filled star filled star filled star
    Glarsynost lives on a planet whose shape is that of a perfect regular dodecahedron. Can you describe the shortest journey she can make to ensure that she will see every part of the planet?