The question is: If you are making a concrete patio 4 inches thick, what is the area of the largest patio you could make if you ordered 2 cubic yards of concrete?

I am a sixth grade teacher and this is an enrichment question for one of my classes If you could answer as soon as possible it would be great. Also, could you please explain how you got the answer.



Hi Anne,

If you knew the length (L), width (W) and thickness (T), all expressed in yards, then the volume of concrete in the patio would be

L W T cubic yards.

You know the volume is 2 cubic yards and hence

L W T = 2 cubic yards.

The thickness is 4 inches and there are 12 inches in a foot so 4 inches is 4/121/3  of a foot. There are 3 feet in a yard so 1/3 of a  foot is 1/3  1/3 = 1/9 of a yard. Hence

L W  1/9 = 2 cubic yards

and thus

L W = 18 square yards.