Final answer:
To cover a floor with an area of 40m², 160 ceramic tiles are needed.
Step-by-step explanation:
To find out how many ceramic tiles are needed to cover a floor of a classroom with an area of 40m², we first need to find the area of a single ceramic tile.
We are given that the area of a single ceramic is 0.25m/s.
To find the number of tiles needed, we divide the total area of the floor by the area of a single tile:
Total area of the floor = 40m²
Area of a single ceramic tile = 0.25m²
Number of ceramic tiles needed = Total area of the floor / Area of a single ceramic tile
= 40m² / 0.25m²
= 160 tiles
Therefore, 160 ceramic tiles are needed to cover the floor of the classroom.