Question 347365
Let's start with how much cement there is: 3x3x3 yard = 9x9x9 feet 729 total 


feet now convert that to inches 729 feet 12 inches to a foot = 8748 inches 



divide that by 3 because its going to be uniformly 3 inches deep all the way 


around, 2916. now its a 25x15 box so 2 sides are 25 and 2 are 15, or a total of 


80 feet around. or 960 inches. 3.0375 inches....rounded to 3 inches so 3 inches 


wide.