Builders will normally order 1 per foot when framing 16" on center to cover the cripples and corners. This does not include the wood required for the bottom and top plate.
144/8
25
144/8 = 18
Standard studs are spaced 16" apart. 30 feet times 12 inches = 360 inches. 360 inches divided by 16 inches = 22.5. If you are measuring left to right, the right-side stud from the frame becomes the last one. Depending on how you will compensate for the extra 8" at the end, you will need 21 or 22 2x4s.
If you have an eight square foot area, and the tiles are 112x12-inches, you will need eight. If what you meant to say was an eight foot square area, that would be 64 square feet, and you would need 64 tile. Sorry! In the first line above should read, "...and the tiles are 12x12-inches..."
There are 12 inches in 1 foot, and 144 inches in 1 square foot (12x12=144). Therefore there are 2.4x144=345.6 square inches in 2.4 square feet.
25
144/8 = 18
144 12x12
Since a 12x12 tile is one square foot, then 38 12x12 tiles will cover 38 square feet.
80 if the tiles are 12x12 - 12x12 is one square foot covering 80 you would need 80 tiles
585
A 12x12 tile is 1 sq foot, so you will need 198 tiles.
3
exactly 8
144 !
12X12=1 Square Foot of tile. You would need 49 Square Feet of tile.
Gee, a square foot is 12x12, difficult problem.