Visualising and representing

  • Filling the gaps
    problem
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    Filling the Gaps

    Age
    14 to 16
    Challenge level
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    Which numbers can we write as a sum of square numbers?

  • Attractive Tablecloths
    problem
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    Attractive Tablecloths

    Age
    14 to 16
    Challenge level
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    Charlie likes tablecloths that use as many colours as possible, but insists that his tablecloths have some symmetry. Can you work out how many colours he needs for different tablecloth designs?

  • Which list is which?
    problem
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    Which List Is Which?

    Age
    14 to 16
    Challenge level
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    Six samples were taken from two distributions but they got muddled up. Can you work out which list is which?

  • Pythagoras Perimeters
    problem
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    Pythagoras Perimeters

    Age
    14 to 16
    Challenge level
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    If you know the perimeter of a right angled triangle, what can you say about the area?

  • Puzzling Place Value
    problem
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    Puzzling Place Value

    Age
    14 to 16
    Challenge level
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    Can you explain what is going on in these puzzling number tricks?

  • The square top of a red gift box with a bow.
    problem
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    Square Number Surprises

    Age
    14 to 16
    Challenge level
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    There are unexpected discoveries to be made about square numbers...

  • Ladder and Cube
    problem
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    Ladder and Cube

    Age
    14 to 16
    Challenge level
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    A 1 metre cube has one face on the ground and one face against a wall. A 4 metre ladder leans against the wall and just touches the cube. How high is the top of the ladder above the ground?

  • Bendy Quad
    problem
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    Bendy Quad

    Age
    14 to 16
    Challenge level
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    Four rods are hinged at their ends to form a convex quadrilateral. Investigate the different shapes that the quadrilateral can take. Be patient this problem may be slow to load.

  • Hexy-Metry
    problem
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    Hexy-Metry

    Age
    14 to 16
    Challenge level
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    A hexagon, with sides alternately a and b units in length, is inscribed in a circle. How big is the radius of the circle?

  • Far Horizon
    problem
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    Far Horizon

    Age
    14 to 16
    Challenge level
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    An observer is on top of a lighthouse. How far from the foot of the lighthouse is the horizon that the observer can see?