How is the volume of concrete needed calculated?

To calculate the volume of concrete needed, one must consider the dimensions of the area where the concrete will be poured. The correct approach involves multiplying the width by the length and the thickness of the concrete layer. This calculation gives you the volume in cubic inches. The division by 12 is necessary when converting from cubic inches to cubic feet since there are 12 inches in a foot.

This method is straightforward and ensures that all dimensions are factored correctly into the volume measurement. By using the product of width, length, and thickness, you can accurately determine how much concrete is needed for a given area, making it a fundamental aspect of planning for projects involving concrete work.

The other options do not accurately reflect the principle of calculating volume based on three-dimensional dimensions. For example, simply multiplying cubic feet by 27 does not provide a volume of concrete needed unless you already have a measurement in cubic feet, and adding dimensions together does not yield a volumetric measurement. Thus, the outlined method in the correct answer is essential for accurate volume calculation.