(5 x 6 x 1.5) = 45 cubic feet = (1 and 2/3) cubic yards
24 cubic feet . . . (6'x6'x 0.67')
6.2 cubic feet
That would take 250 cubic meters of sand to fill as 10*5*5 is 250.
find the area of it 320 feet squared
Assuming the box was empty to begin with there will be 8 inches of sand now.
24 cubic feet . . . (6'x6'x 0.67')
It will take 72 sq. ft. of sand. Or 2.66 sq. yds. That will fill the box even.
6.2 cubic feet
That would take 250 cubic meters of sand to fill as 10*5*5 is 250.
36 cubic feet of dirt=)
96 cubic feet
find the area of it 320 feet squared
12 sq yds
Assuming the box was empty to begin with there will be 8 inches of sand now.
1 foot by 36 sq feet = 36 cubic feet of dirt is needed
In order to answer this question you must first convert the measurements into inches(20 ft= 240 in), so the new problem is 240*240*3, which equals 172800. Then you must convert the inches into yards by dividing 172800 by 36, which equals 4800. So it takes 4800 yards of sand to fill a sandbox 20 feet by 20 feet by 3 inches.
Call around to your local lumber yards and garden supply centers to get a price on a ton of sand. In my area of Pennsylvania it was going for around $30 a ton plus delivery. This was to fill a large 5' x 5' sandbox we made under a treehouse. If you are going with a much smaller sand box you might just want to buy a few bags of sandbox sand which I have seen for $2 to $4 each depending on the size. Jim