Year 9 Exploring and noticing

  • problem
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    Cyclic Quadrilaterals

    Age
    11 to 16
    Challenge level
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    Draw some quadrilaterals on a 9-point circle and work out the angles. Is there a theorem?

  • problem
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    Marbles in a Box

    Age
    11 to 16
    Challenge level
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    How many winning lines can you make in a three-dimensional version of noughts and crosses?

  • Wipeout
    problem
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    Wipeout

    Age
    11 to 16
    Challenge level
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    Can you do a little mathematical detective work to figure out which number has been wiped out?

  • Triangle in a Trapezium
    problem
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    Triangle in a Trapezium

    Age
    11 to 16
    Challenge level
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    Can you find and prove the relationship between the area of a trapezium and the area of a triangle constructed within it?

  • Generating Triples
    problem
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    Generating Triples

    Age
    14 to 16
    Challenge level
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    Sets of integers like 3, 4, 5 are called Pythagorean Triples, because they could be the lengths of the sides of a right-angled triangle. Can you find any more?

  • Tree tops
    problem
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    Tree Tops

    Age
    14 to 16
    Challenge level
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    Can you make sense of information about trees in order to maximise the profits of a forestry company?

  • Tet-Trouble
    problem
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    Tet-Trouble

    Age
    14 to 16
    Challenge level
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    Is it possible to have a tetrahedron whose six edges have lengths 10, 20, 30, 40, 50 and 60 units?