Each tile covers a square foot. So you need 542, plus some for spoilage and cutting.
Since a 12x12 tile is one square foot, then 38 12x12 tiles will cover 38 square feet.
A 12x12 inch paver is one square foot. So you would need 240 square feet.
A A 12x12 sq feet tile covers 144 sq feet. So to cover 1200 sq feet you will need 1200/144 = 8.3 or 9 tiles.
144 square feet.
Since each 12x12-inch tile is one square foot, you will need 750 of them.