Combinations

  • Trominoes
    problem

    Trominoes

    Age
    11 to 16
    Challenge level
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    Can all but one square of an 8 by 8 Chessboard be covered by Trominoes?
  • Flora the Florist
    problem

    Flora the Florist

    Age
    14 to 16
    Challenge level
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    Flora has roses in three colours. What is the greatest number of identical bunches she can make, using all the flowers?

  • Coin Tossing Games
    problem

    Coin Tossing Games

    Age
    14 to 16
    Challenge level
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    You and I play a game involving successive throws of a fair coin. Suppose I pick HH and you pick TH. The coin is thrown repeatedly until we see either two heads in a row (I win) or a tail followed by a head (you win). What is the probability that you win?

  • Cross-Country Race
    problem

    Cross-Country Race

    Age
    14 to 16
    Challenge level
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    Eight children enter the autumn cross-country race at school. How many possible ways could they come in at first, second and third places?

  • The Olympic Torch Tour
    problem

    The Olympic Torch Tour

    Age
    14 to 16
    Challenge level
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    Imagine you had to plan the tour for the Olympic Torch. Is there an efficient way of choosing the shortest possible route?

  • Scratch Cards
    problem

    Scratch Cards

    Age
    14 to 16
    Challenge level
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    To win on a scratch card you have to uncover three numbers that add up to more than fifteen. What is the probability of winning a prize?

  • Factoring a million
    problem

    Factoring a Million

    Age
    14 to 16
    Challenge level
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    In how many ways can the number 1 000 000 be expressed as the product of three positive integers?

  • Spectrometry detective
    problem

    Spectrometry Detective

    Age
    16 to 18
    Challenge level
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    From the atomic masses recorded in a mass spectrometry analysis can you deduce the possible form of these compounds?
  • The Secret World of Codes and Code Breaking
    article

    The Secret World of Codes and Code Breaking

    When you think of spies and secret agents, you probably wouldn’t think of mathematics. Some of the most famous code breakers in history have been mathematicians.