Reflections

  • ...on the wall
    problem
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    ...on the Wall

    Age
    11 to 14
    Challenge level
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    Explore the effect of reflecting in two intersecting mirror lines.

  • Surprising Transformations
    problem
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    Surprising Transformations

    Age
    14 to 16
    Challenge level
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    I took the graph y=4x+7 and performed four transformations. Can you find the order in which I could have carried out the transformations?

  • 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?

  • Cushion Ball
    problem

    Cushion Ball

    Age
    16 to 18
    Challenge level
    filled star empty star empty star
    The shortest path between any two points on a snooker table is the straight line between them but what if the ball must bounce off one wall, or 2 walls, or 3 walls?
  • Retracircles
    problem

    Retracircles

    Age
    16 to 18
    Challenge level
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    Four circles all touch each other and a circumscribing circle. Find the ratios of the radii and prove that joining 3 centres gives a 3-4-5 triangle.
  • Rots and Refs
    problem

    Rots and Refs

    Age
    16 to 18
    Challenge level
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    Follow hints using a little coordinate geometry, plane geometry and trig to see how matrices are used to work on transformations of the plane.
  • Hidden Meaning
    problem

    Hidden Meaning

    Age
    7 to 11
    Challenge level
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    What is the missing symbol? Can you decode this in a similar way?
  • Patchwork Quilt
    problem

    Patchwork Quilt

    Age
    7 to 14
    Challenge level
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    Squares of the type shown are sewn together to make a quilt. How many different quilts can be made?
  • Tricircle
    problem

    Tricircle

    Age
    14 to 16
    Challenge level
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    The centre of the larger circle is at the midpoint of one side of an equilateral triangle and the circle touches the other two sides of the triangle. A smaller circle touches the larger circle and two sides of the triangle. If the small circle has radius 1 unit find the radius of the larger circle.
  • Two triangles in a Square
    problem

    Two Triangles in a Square

    Age
    14 to 16
    Challenge level
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    Given that ABCD is a square, M is the mid point of AD and CP is perpendicular to MB with P on MB, prove DP = DC.