Combining probabilities

  • Dicey Decisions
    problem

    Dicey decisions

    Age
    16 to 18
    Challenge level
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    Can you devise a fair scoring system when dice land edge-up or corner-up?
  • At least one...
    problem

    At least one...

    Age
    11 to 14
    Challenge level
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    Imagine flipping a coin a number of times. Can you work out the probability you will get a head on at least one of the flips?

  • Same Number!
    problem

    Same number!

    Age
    14 to 16
    Challenge level
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    If everyone in your class picked a number from 1 to 225, do you think any two people would pick the same number?
  • Molecular sequencer
    problem

    Molecular sequencer

    Age
    14 to 18
    Challenge level
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    Investigate the molecular masses in this sequence of molecules and deduce which molecule has been analysed in the mass spectrometer.
  • Heavy hydrocarbons
    problem

    Heavy hydrocarbons

    Age
    14 to 18
    Challenge level
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    Explore the distribution of molecular masses for various hydrocarbons
  • Taking Chances
    problem

    Taking chances

    Age
    11 to 14
    Challenge level
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    This article, for students and teachers, is mainly about probability, the mathematical way of looking at random chance and is a shorter version of Taking Chances Extended.
  • The Better Choice
    problem

    The better choice

    Age
    14 to 16
    Challenge level
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    Here are two games you can play. Which offers the better chance of winning?
  • Put Out
    problem

    Put out

    Age
    16 to 18
    Challenge level
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    After transferring balls back and forth between two bags the probability of selecting a green ball from bag 2 is 3/5. How many green balls were in bag 2 at the outset?
  • Voting Paradox
    problem

    Voting paradox

    Age
    14 to 18
    Challenge level
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    Some relationships are transitive, such as `if A>B and B>C then it follows that A>C', but some are not. In a voting system, if A beats B and B beats C should we expect A to beat C?