Using this online activity, students explore the meaning of probability using the pigeonhole principle. The initial question asks students to determine the probability that someone who is not paying attention to what she is doing can put checks into the correct envelopes. The activity is one of 80 mathematical challenges featured on the Figure This! web site, where real-world uses of mathematics are emphasized. The solution hint suggests experimenting with the possible outcomes with checks a, b, and c and envelopes A, B, and C. The solution is explained using three different approaches: a table, a tree diagram, and geometry. In related questions, students investigate probability when tossing a coin, rolling a die, and when guessing answers on tests. Information about the history of probability and its use for predicting events is also included on the site. Copyright 2005 Eisenhower National Clearinghouse


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Informal Education,Process skills,Middle School,NSDL,Probability,Grade 8,Grade 7,NSDL_SetSpec_1007936,Grade 6,Problem solving,Mathematics,Strategies,Education,oai:nsdl.org:2200/20120114184526322T



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