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A team of students has finished an investigation on the many uses of parabolas. They must select a single group member to present their findings to the class. They have only a single coin to make chance selections, but they can flip it as many times as necessary to select a student fairly. 

  1. Using a single coin, find a fair way to select the presenter.

    There are a variety of possible methods. Make sure each student has an equally likely chance of being selected.

  2. What is the smallest number of coin tosses needed to select a presenter fairly? Describe the method.

    Draw a tree diagram.
    How many times does the coin need to be flipped to get a sample space of equally likely outcomes?

  3. Two of the group members realize they won’t be in class the day of the presentation because they are playing in a baseball tournament. Can a presenter still be chosen fairly with a single coin? Explain why or why not?

    Yes. Explanations/methods will vary.