Hello There!
Great Question!
To calculate the area of a rectangular prism, you would multiply the length, the width, and the depth. As we want to measure this in cubic feet, we should convert all of the measurements to feet to begin with.
How wide is the garden? (either 7 or 8 feet)
How long is the garden? (Whichever of 7 or 8 wasn’t used)
How deep is this garden? 6 inches.
Well, that’s not feet, right?
How many inches are in a foot? 12.
Divide 6 by 12, what is the answer? .5.