The answer to this all depends on the size of the bricks.
8
60
400 bricks
198
no .of bricks = area of room /area of bricks area of room = 9 X12 X12 X12 inches ( 1 foot =12 inches ) area of bricks =3 X8 no.0f bricks =9 X12 X12 X12 inches /3 X 8 =648
240
180
Assuming the bricks are 4 inches wide and 16 inches long. Then the area of one brick is 64 square inches = 64/144 = 4/9 square feet, hence to cover 640 square feet we need (640)/(4/9) = (640x9)/4 = 160x 9 = 1440
15
42
it will take 1.33 2x6s to cover 16 feet.
15 exactly !