This web page presents the puzzle, "The Ruler that Missed the Mark" from The Museum of Mathematics' traveling exhibit, "Math Midway.” The exhibit allows visitors to explore the world of pattern, shape and numbers. Visitors are given a ruler that is 8 inches long and has a mark at 1, 3 and 7 inches and are asked, "How can you use this ruler to measure any whole number of inches from 1 to 8?” The problem is then extended to "What's the fewest number of marks one could put on a 12-inch ruler and still be able to measure every distance from 1 inch to 12 inches?" Solutions are linked to the page.


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