Two students agree to meet up in a bar. They are both trying to be very precise, and try to arrive at exactly the right time, but arrive 29 minutes apart. An example of the ambiguities of language unfolds, which shows why mathematics needs to use algebraic symbols. Marcus du Sautoy sets the problem in this puzzle panel game.
Could be used as a starter activity, perhaps to lead on to a discussion of the problems of language, and how algebraic notation is an attempt to avoid any ambiguities.