Equally likely outcomes

  • 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?
  • Coin Tossing Games
    problem

    Coin tossing games

    Age
    14 to 16
    Challenge level
    filled star filled star empty star
    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?
  • Teams
    problem

    Teams

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

    Two brothers belong to a club with 10 members. Four are selected for a match. Find the probability that both brothers are selected.

  • A Brief History of Probability
    problem

    A brief history of probability

    Age
    11 to 14
    Challenge level
    filled star empty star empty star

    Can you help d'Alembert discover the probabilty of at least one head in two coin flips?