This activity introduces students to radar bills (currency that has serial numbers that read the same forward and backward) and challenges them to estimate how frequently radar bills occur. The activity, part of the Figure This! collection of 80 math challenges emphasizing math in the real world, explains how symmetry and repeating patterns are important to mathematicians, scientists, and artists. The Hint tells students that our currency has eight-digit serial numbers, and the solution provides a table that shows the relationship between the number of digits in a serial number and the number of radar bills. Related questions ask students to solve similar problems with serial numbers that contain different numbers of digits. Answers to all questions and links to additional resources are provided. Copyright 2005 Eisenhower National Clearinghouse


  • Mathematics > General

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Informal Education,Number and operations,Middle School,NSDL,Grade 8,NSDL_SetSpec_1007936,Grade 6,oai:nsdl.org:2200/20120114184631463T,Number patterns,Mathematics,Patterns and sequences,Grade 7



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