What is the difference in elevation between Point "A" and Point "B", if the elevation drops 1/8 inch every foot over 250 feet?

To determine the difference in elevation between Point "A" and Point "B" given that the elevation drops 1/8 inch every foot over a distance of 250 feet, we can break the problem down into two parts: the rate of drop and the total distance.

First, the elevation drop is specified as 1/8 inch for every foot. Thus, to find the total drop over 250 feet, you multiply the drop per foot (1/8 inch) by the total distance (250 feet):

1/8 inch per foot × 250 feet = 250/8 inches.

Calculating that gives:

250 ÷ 8 = 31.25 inches.

This value can also be expressed as 31-1/4 inches, which matches the correct answer. Therefore, the difference in elevation between Point "A" and Point "B" is indeed 31-1/4 inches. This illustrates a clear understanding of how to apply the rate of elevation change over a specified distance, which is essential in grading and excavation practices.