Answer / soumya

N=E*A/(F*U.F*L.L.F); N= number of light fittings required;

E = Lux required in working plane
A = Area of the room
F = Total Flux (Lumens) from all the Lamps in one Fitting
UF = Utilisation Factor = 0.46 (approx)
LLF = Light Loss Factor OR maintenance factor = 0.8 (approx)

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