Conjecturing and generalising

  • Odd Differences
    problem
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    Odd Differences

    Age
    14 to 16
    Challenge level
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    The diagram illustrates the formula: 1 + 3 + 5 + ... + (2n - 1) = n² Use the diagram to show that any odd number is the difference of two squares.

  • Expenses
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    Expenses

    Age
    14 to 16
    Challenge level
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    What is the largest number which, when divided into these five numbers in turn, leaves the same remainder each time?

  • Plus Minus
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    Plus Minus

    Age
    14 to 16
    Challenge level
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    Can you explain the surprising results Jo found when she calculated the difference between square numbers?

  • Of all the areas
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    Of All the Areas

    Age
    14 to 16
    Challenge level
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    Can you find a general rule for finding the areas of equilateral triangles drawn on an isometric grid?

  • Fair Shares?
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    Fair Shares?

    Age
    14 to 16
    Challenge level
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    A mother wants to share some money by giving each child in turn a lump sum plus a fraction of the remainder. How can she do this to share the money out equally?

  • What's Possible?
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    What's Possible?

    Age
    14 to 16
    Challenge level
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    Many numbers can be expressed as the difference of two perfect squares. What do you notice about the numbers you CANNOT make?

  • Why 24?
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    Why 24?

    Age
    14 to 16
    Challenge level
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    Take any prime number greater than 3 , square it and subtract one. Working on the building blocks will help you to explain what is special about your results.

  • Gnomon dimensions
    problem

    Gnomon Dimensions

    Age
    14 to 16
    Challenge level
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    These gnomons appear to have more than a passing connection with the Fibonacci sequence. This problem ask you to investigate some of these connections.
  • Overlap
    problem

    Overlap

    Age
    14 to 16
    Challenge level
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    A red square and a blue square overlap. Is the area of the overlap always the same?

  • Pick's Theorem
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    Pick's Theorem

    Age
    14 to 16
    Challenge level
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    Polygons drawn on square dotty paper have dots on their perimeter (p) and often internal (i) ones as well. Find a relationship between p, i and the area of the polygons.