Experimental probability S1.3 Core Plenary Sitting at tables Amy studies the ways people behave. She is interested in how two people sit round a square table where one person can sit at each side. They can either sit facing each other or sit beside each other. e.g. or Here are some of the results of her observations. Investigate Amy’s claim that: “My results show that there is no pattern in how two people sit round a table. Where they sit is random.” Preamble This whole-class activity will allow pupils the opportunity to compare a set of experimental results with the expected results based on simple probability analysis of the situation. Encourage initial discussion as to how to attack the problem – some pupils will need support here. Set this in train by looking at the experimental results – “What do they suggest?” (probabilities are roughly equal). The activity could become a real practical investigation based on seating in the dinning room perhaps. Possible content Comparing experimental and theoretical probabilities. Working systematically. The role that randomness plays in probability. Resources Squared paper. Solution/Notes From the diagram it can be seen that the probability of sitting opposite someone by chance is . The experimental results give about a 50% probability which suggests that people do not sit at random they prefer face to face. Original Material © Cambridge University Press 2009