This Technology Problem of the Week (tPoW) presents a puzzle also known as Hop, Skip, Jump: five people in a row, each on a stepping stone, facing five others on stepping stones of their own, with the two groups separated by an eleventh, empty stepping stone in the middle. The challenge: exchanging places by "jumping" people one at a time onto an unoccupied stepping stone, so that the people originally standing on the righthand stepping stones are on the lefthand ones, and vice versa. The question: What's the fewest number of moves for 10 people (5 people on each side) to end up on the opposite side from where they started? What hints or strategies would you give someone to help them find the fewest number of moves? This tPoW links to the Java applet "Traffic Jam." Solve and explain your solution; download hints and answer checks. Free registration is required. Also available in Spanish.


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Informal Education,Process skills,Number and operations,Make use of structure,NSDL,Upper Elementary,NSDL_SetSpec_ncs-NSDL-COLLECTION-000-003-112-027,Grade 5,Strategies,Number patterns,Elementary School,Mathematics,Grade 4,Engineering,Education,Problem solving,Discrete mathematics,oai:nsdl.org:2200/20140728160638034T,Recursion and iteration,Patterns and sequences,Practice Standards



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