Working systematically

  • Matchless
    problem

    Matchless

    Age
    14 to 16
    Challenge level
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    There is a particular value of x, and a value of y to go with it, which make all five expressions equal in value, can you find that x, y pair ?

  • Inside Triangles
    problem

    Inside triangles

    Age
    5 to 7
    Challenge level
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    How many different triangles can you draw which each have one dot in the middle?

  • Nicely Similar
    problem

    Nicely similar

    Age
    14 to 16
    Challenge level
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    If the hypotenuse (base) length is 100cm and if an extra line splits the base into 36cm and 64cm parts, what were the side lengths for the original right-angled triangle?

  • Route Product
    problem

    Route product

    Age
    7 to 11
    Challenge level
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    Find the product of the numbers on the routes from A to B. Which route has the smallest product? Which the largest?

  • Constellation Sudoku
    problem

    Constellation Sudoku

    Age
    14 to 18
    Challenge level
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    Special clue numbers related to the difference between numbers in two adjacent cells and values of the stars in the "constellation" make this a doubly interesting problem.

  • Knights moving
    problem

    Knights moving

    Age
    16 to 18
    Challenge level
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    Can you swap the black knights with the white knights in the minimum number of moves?
  • Ratio Sudoku 3
    problem

    Ratio Sudoku 3

    Age
    11 to 16
    Challenge level
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    A Sudoku with clues as ratios or fractions.

  • Integrated Product Sudoku
    problem

    Integrated product Sudoku

    Age
    11 to 16
    Challenge level
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    This Sudoku puzzle can be solved with the help of small clue-numbers on the border lines between pairs of neighbouring squares of the grid.

  • Growing Garlic
    problem

    Growing garlic

    Age
    5 to 11
    Challenge level
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    Ben and his mum are planting garlic. Can you find out how many cloves of garlic they might have had?