2 inch thick 5 x 5 area

These bags do not fill large areas. I filled an area about 5x2 by 2 inches. I used 10 bags! It was expensive! These bags are good for small holes, not large ones. Find a quarry and pick it up yourself or have a paving co. come by after they finish a big job with some left over.

You will need 13 bags. 5' x 5' x 2" = 4.2 cubic feet. Each bag contains 1/3 cu-ft. 4.2 x 3 = 13 bags The .75 square feet is a piece of useless information, although the answer to your question is about 5-1/4".