-The Floor Area Ratio (FAR) or Floor Space Index (FSI) is the ratio of the total floor area of buildings on a certain location to the size of the land of that location, or the limit imposed on such a ratio.
As a formula: Floor Area Ratio = (Total covered area on all floors of all buildings on a certain plot)/(Area of the plot)
Thus, an FSI of 2.0 would indicate that the total floor area of a building is two times the gross area of the plot on which it is constructed, as would be found in a multiple-story building.
first multiply 110x100=11000 then multiply11000sqft total plot area by ur fsi in ur case 1.9 results is 20900 tht the total builtup area. now ur case 1stilt floor + 4floors.thts 20900 divided by 5 = 4180 on each floor.assume 4flats on each floor 2 1bhk 600sqft & 2 2bhk 900sqft rest for lift n stairs