One 12 ft x 12 ft tile will be more than big enough!
A 10'-0" X 10'-0" area is 120" X 120". 120" divided by 16" = 7.5 tiles. Therefore your room is 7.5 tiles X 7.5 tiles. This equates to 49 full tiles + 14 half tiles (or 7 full tiles) + a tile for the one corner. This totals 57 tiles. I would add extra to cover mistakes when cutting the tiles - check quantity per package and round up.
120 square feet
If this is a practical question, "considerably less than one" should be a sufficient answer. If it's a math question, do your own homework.