Illinois Real Estate Practice Exam 2025 - Free Real Estate Practice Questions and Study Guide

To determine the total volume of concrete needed for the patio, we first need to convert all measurements to the same unit. The dimensions are given as 15 feet in width, 20 feet in length, and 6 inches in depth. Since the depth is in inches, we convert it to feet:

6 inches = 0.5 feet.

Next, to calculate the volume in cubic feet, we use the formula for the volume of a rectangular prism:

Volume = Width × Length × Depth.

Substituting in the dimensions:

Volume = 15 ft × 20 ft × 0.5 ft = 150 cubic feet.

Since concrete is typically measured in cubic yards, we convert cubic feet to cubic yards. There are 27 cubic feet in a cubic yard, so we divide the volume in cubic feet by 27:

150 cubic feet ÷ 27 ≈ 5.56 cubic yards.

The closest whole number to this amount is 6 cubic yards. Therefore, the total volume of concrete needed for the patio is 6 cubic yards.

This calculation confirms that the answer is indeed the correct one, aligning with proper measurement conversion and volume calculation methods.