Tree diagrams

  • Same Number!
    problem

    Same number!

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

    Succession in Randomia

    Age
    16 to 18
    Challenge level
    filled star empty star empty star

    By tossing a coin one of three princes is chosen to be the next King of Randomia. Does each prince have an equal chance of taking the throne?

  • Interactive Spinners
    problem

    Interactive spinners

    Age
    11 to 14
    Challenge level
    filled star empty star empty star
    This interactivity invites you to make conjectures and explore probabilities of outcomes related to two independent events.
  • Odds and Evens
    problem

    Odds and evens

    Age
    11 to 14
    Challenge level
    filled star empty star empty star
    Are these games fair? How can you tell?
  • Flippin' discs
    problem

    Flippin' discs

    Age
    11 to 14
    Challenge level
    filled star empty star empty star
    Discs are flipped in the air. You win if all the faces show the same colour. What is the probability of winning?
  • Chances are
    problem

    Chances are

    Age
    14 to 16
    Challenge level
    filled star empty star empty star
    Which of these games would you play to give yourself the best possible chance of winning a prize?
  • In a box
    problem

    In a box

    Age
    14 to 16
    Challenge level
    filled star filled star empty star
    Chris and Jo put two red and four blue ribbons in a box. They each pick a ribbon from the box without looking. Jo wins if the two ribbons are the same colour. Is the game fair?
  • Master Minding
    problem

    Master minding

    Age
    11 to 14
    Challenge level
    filled star filled star empty star
    Your partner chooses two beads and places them side by side behind a screen. What is the minimum number of guesses you would need to be sure of guessing the two beads and their positions?
  • Squash
    problem

    Squash

    Age
    16 to 18
    Challenge level
    filled star filled star filled star
    If the score is 8-8 do I have more chance of winning if the winner is the first to reach 9 points or the first to reach 10 points?
  • Rain or Shine
    problem

    Rain or shine

    Age
    16 to 18
    Challenge level
    filled star filled star empty star
    Predict future weather using the probability that tomorrow is wet given today is wet and the probability that tomorrow is wet given that today is dry.