When graphing points on a number line, one can graph all points up to and including a point by using a line that ends with a closed circle, but can indicate all points up to, but not including that point by instead ending with an open circle. In the later case, one can get as close to the end point as possible without hitting that point, making the difference between the point and any chosen point infinitesimally small. I thought of this concept this past week when I heard of a proposal about grading parents of students that was proposed by a legislator from Florida.

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