This is a game based on David Cox's nice percent estimation sketch: [url]http://www.geogebratube.org/material/show/id/21629[/url][br][br]Using it in class students immediately turned it into a game. But it was tough because the 2nd person always got to use the helpful markings.[br][br]So I made it into a game! David's sketch is - of course - perfect practice or warm up for the game.

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