The volume of sand weighs 455x 2/12 *100 pounds per cubic foot = 7600 pounds so you need about 152 bags.
6.14 x 2.61 = 16.0254 square inches = 0.00000000399188978 square miles x 1000000000 = 3.99188978 square miles. Call it 4 square miles.
One square foot would be 12 inches by 12 inches, or 144 square inches. This means to convert square feet to square inches, multiply the number of square feet by 144 to to get the number of square inches.
The square root of 225 is 15 so the answer would be 15 inches.
One 9 inch square tile would presumably be 9in x 9in or 81in2, unless you are meaning 3in x 3in tile which is then 9in2. Regardless, the answer to your question is the total area of the floor (in square inches) divided by the total area of one tile (in square inches).
A pound coin is 22½ mm diameter, while a football pitch is approximately 100 x 40 metres, so 4000 square metres. Each coin fits in a 22½ mm square, which is an area of 0.0225 x 0.0225 square metres. That is .0005 square metres. The ratio of the areas is 4000 / .0005 so that football pitch would take 7.9 million pound coins.
Three square feet would cover one square yard or 36 square inches.
If they 16 is in inches, this would be 256 square inches per tile. That would cover 10,496 square inches. Divide by 144 and you get 72.89 square feet.
1 cubic yard covers 324 square feet per inch of thickness, divide 324 by thickness in inches to get coverage, i.e. 4 inches thick would cover 324/4=81 square feet, 36 inches thick would cover (you guessed it) 9 square feet.
Each brick is 27 square inches. 27*434=11,718 square inches of bricks.
Approximately 73 square feet.
If your tiles are 12 inches x 12 inches you would need 144 of them.
Easy way to figure it: If the roll is 3 feet by 100 feet, it would cover 300 square feet. But you have to overlap it about 6 inches at top and bottom, so once you subtract that, it would cover about 200 square feet., When figuring a job, add some for overlap at valleys, chimneys, etc. . . Hope this helps. A standard roll of 30# felt covers 216 square feet; one-half the area of a roll of 15# felt, which covers 432 square feet. Rows are overlapped 2 inches, not 6 inches.
11 feet x 14 feet = 154 square feet. You would need 9 tiles, that measured 4 inches x four inches, to cover one square foot. So you would need 154 x 9 tiles to cover the entire area, which is 1386 tiles.
One bag would cover 250 square feet to a depth of 1/125 = 0.008 feet = 0.96 inches.
You would need 31, 80 pound bags to cover 1 cubic yard at 4 inches deep. If you would like the depth to be 6 inches, 45 bags would be needed.
It would take roughly 66 bags to cover a 200 square ft area 2 inches thick
I would guess about 70-80 bales