Answer:
Total cost of polishing the floor is Rs/500.
Explanation:
The floor consists of 2000 tiles which have the shape of a rhombus.
Area of rhombus =

Where:
and
are the diagonals.
Given that:
= 40 cm = 0.4 m
= 25 cm = 0.25 m
Then,
Area of each tile =

=

= 0.05

Area of each tile is 0.05
.
Since there are 2000 tiles on the floor of the building, then;
Total area covered by the tiles = 0.05 x 2000
= 100

The total cost of polishing the floor = 100 x Rs/5
= Rs/500