This activity asks the student to find the number of possible combinations for a lock showing the numbers 0 to 39. It is part of the Figure This! collection of 80 online mathematical challenges emphasizing real world uses of mathematics. The solution to the combination question applies the technique of using a smaller number of possible arrangements to study a problem. Students learn to use a tree diagram to model possible outcomes and explore the mathematical meaning of the term combination. They are further challenged to determine the number of possible combinations for other types of locks and to find the total number of phone numbers possible for an area code. The activity includes a solution hint, family activities, and a list of resources related to locks. Copyright 2005 Eisenhower National Clearinghouse


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Informal Education,Process skills,Combinations and permutations,Middle School,NSDL,Probability,Grade 8,NSDL_SetSpec_1007936,Grade 6,Mathematics,Real world applications,Education,Reasoning,oai:nsdl.org:2200/20120114184516999T,Grade 7



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