Visualising and representing

  • Legs Eleven
    problem

    Legs eleven

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

    Take any four digit number. Move the first digit to the end and move the rest along. Now add your two numbers. Did you get a multiple of 11?

  • Crossing the Atlantic
    problem

    Crossing the atlantic

    Age
    11 to 14
    Challenge level
    filled star filled star empty star
    Every day at noon a boat leaves Le Havre for New York while another boat leaves New York for Le Havre. The ocean crossing takes seven days. How many boats will each boat cross during their journey?
  • Hallway Borders
    problem

    Hallway borders

    Age
    11 to 14
    Challenge level
    filled star filled star filled star
    What are the possible dimensions of a rectangular hallway if the number of tiles around the perimeter is exactly half the total number of tiles?
  • Tic Tac Toe
    problem

    Tic tac toe

    Age
    11 to 14
    Challenge level
    filled star filled star empty star
    In the game of Noughts and Crosses there are 8 distinct winning lines. How many distinct winning lines are there in a game played on a 3 by 3 by 3 board, with 27 cells?
  • Hypotenuse Lattice points
    problem

    Hypotenuse lattice points

    Age
    14 to 16
    Challenge level
    filled star filled star filled star
    The triangle OMN has vertices on the axes with whole number co-ordinates. How many points with whole number coordinates are there on the hypotenuse MN?
  • Painting Cubes
    problem

    Painting cubes

    Age
    11 to 14
    Challenge level
    filled star filled star filled star
    Imagine you have six different colours of paint. You paint a cube using a different colour for each of the six faces. How many different cubes can be painted using the same set of six colours?
  • A Problem of time
    problem

    A problem of time

    Age
    14 to 16
    Challenge level
    filled star filled star filled star
    Consider a watch face which has identical hands and identical marks for the hours. It is opposite to a mirror. When is the time as read direct and in the mirror exactly the same between 6 and 7?
  • Face Painting
    problem

    Face painting

    Age
    7 to 11
    Challenge level
    filled star filled star empty star
    You want to make each of the 5 Platonic solids and colour the faces so that, in every case, no two faces which meet along an edge have the same colour.
  • Dissect
    problem

    Dissect

    Age
    11 to 14
    Challenge level
    filled star filled star filled star
    What is the minimum number of squares a 13 by 13 square can be dissected into?
  • Chess
    problem

    Chess

    Age
    11 to 14
    Challenge level
    filled star filled star empty star
    What would be the smallest number of moves needed to move a Knight from a chess set from one corner to the opposite corner of a 99 by 99 square board?