What is the volume of a drainfield that is 50 feet by 90 feet and covered with sand loam averaging 15 inches?

To determine the volume of a drainfield that measures 50 feet by 90 feet and has a thickness of 15 inches, it's essential to convert all measurements to the same unit and then use the volume formula for a rectangular prism, which is length times width times height.

First, convert the dimensions:

• The area is calculated by multiplying the length and width:

50 feet * 90 feet = 4500 square feet.

Next, convert the depth of 15 inches to feet, since there are 12 inches in a foot:

• 15 inches / 12 = 1.25 feet.

Now, you can find the volume:

• Volume = Area * Depth

= 4500 square feet * 1.25 feet = 5625 cubic feet.

To convert cubic feet to cubic yards (since there are 27 cubic feet in a cubic yard):

• 5625 cubic feet / 27 = approximately 208.33 cubic yards.

Thus, the correct answer indicating the volume of the drainfield is approximately 208.3 cubic yards. This reasoning aligns with the correct answer and demonstrates the necessary calculations and conversions needed to arrive at the solution.