Length of one diagonal, d1 = 45 cm and d2 = 30 cm
∵ Area of one tile =(12)d1d2
=(12)×45×30=675cm2
Area of one tile is 675 cm2
Area of 3000 tiles is
=675×3000=2025000 cm2
=202500010000
=202.50 m2[∵1m2=10000 cm2]
∵ Cost of polishing the floor per sq. meter = Rs 4
Cost of polishing the floor per 202.50 sq. meter = 4 × 202.50 = Rs. 810
Hence the total cost of polishing the floor is Rs. 810.