What is the percent ruler used for and why? 38

 A percent ruler is a tool that we can use to connect percents to other forms of a number.

The ruler postulate tells us how to find the distance between two points. First, we have to match each of the two points to a number. We call these numbers the coordinates of the points. Then, we subtract the coordinates from each other. If the resulting difference is negative, we take the absolute value of the result because the distance is always a positive number.

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