There is 144 sq inches in a square foot... how many sq inches in your brick?
16 x 16 = 256 Sq Ins /144 = 1.78 sq ft per brick 121 / 1.78 = 68 Bricks but I would buy 3 or 4 extra depending on cuts you need to make.
9 tons
1076.391042 sq. ft.
19681.81 sq ft
5220.5 sq ft
32 sq. ft.
The question does not specify the units used for the size of each brick. Assuming the brick's dimensions are given in inches, each brick covers 4" x 8" = 1/3 ft x 2/3 ft = 2/9 sq ft. Area to be covered = 320 sq ft so minimum number of bricks required = 320 / (2/9) = 1440 bricks. That answer assumes that the area to be covered is well behaved and that all offcuts are used.
1 sq yd are in 9 sq ft
3 sq yards = 3*9 sq ft = 27 sq ft
288 sq ft
1120 sq ft