How to Figure Grade Slope
- 1). Measure the entire length of the slope using the tape measure. The end calculation will yield an average grade for the entire slope.
- 2). Measure the change in height over the distance of the slope. Make sure you measure using the same start and end points you used to measure the length of the slope.
- 3). Divide the change in the height of the slope by the distance, which will yield the grade as a percent. For example, if the height is 30 inches and the distance is 120 inches, the result is 0.25 or 25%.
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