Arithmetic sequences

  • What numbers can we make now?
    problem
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    What Numbers Can We Make Now?

    Age
    11 to 14
    Challenge level
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    Imagine we have four bags containing numbers from a sequence. What numbers can we make now?

  • Charlie's delightful machine
    problem
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    Charlie's Delightful Machine

    Age
    11 to 16
    Challenge level
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    Here is a machine with four coloured lights. Can you develop a strategy to work out the rules controlling each light?

  • A little light thinking
    problem
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    A Little Light Thinking

    Age
    14 to 16
    Challenge level
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    Here is a machine with four coloured lights. Can you make two lights switch on at once? Three lights? All four lights?

  • Steel Cables
    problem
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    Steel Cables

    Age
    14 to 16
    Challenge level
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    Some students have been working out the number of strands needed for different sizes of cable. Can you make sense of their solutions?

  • Mystic Rose
    problem
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    Mystic Rose

    Age
    14 to 16
    Challenge level
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    Use the animation to help you work out how many lines are needed to draw mystic roses of different sizes.

  • Prime AP
    problem
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    Prime AP

    Age
    16 to 18
    Challenge level
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    What can you say about the common difference of an AP where every term is prime?

  • Matchsticks
    problem

    Matchsticks

    Age
    7 to 11
    Challenge level
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    Reasoning about the number of matches needed to build squares that share their sides.
  • Summats Clear
    problem

    Summats Clear

    Age
    16 to 18
    Challenge level
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    Find the sum, f(n), of the first n terms of the sequence: 0, 1, 1, 2, 2, 3, 3........p, p, p +1, p + 1,..... Prove that f(a + b) - f(a - b) = ab.
  • content-03-01-cupboardlove2-sol1.gif
    problem

    Transformations Tables

    Age
    7 to 11
    Challenge level
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    These grids are filled according to some rules - can you complete them?
  • Squares, Squares and More Squares
    problem

    Squares, Squares and More Squares

    Age
    11 to 14
    Challenge level
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    Can you dissect a square into: 4, 7, 10, 13... other squares? 6, 9, 12, 15... other squares? 8, 11, 14... other squares?