Answer:

We know that perimeter is the sum of length of the boundary.

We will calculate the number of tiles present at the boundary of floor.

Number of tiles along boundary = 20

Perimeter of floor = 20 units

On checking the boundary,

Length of each tile = 1 unit

Given that the area of each tile = 1 sq. unit

Total number of tiles in the floor = 24

Area of floor = 1 x 24 = 24 sq. units