A floor 5 m by 20 m is covered by square tiles of side 20 cm. How many tiles are needed

number of tiles needed = 2500 pieces

Step-by-step explanation:

Floor area = 5m x 20m = 100 m²

area of 1 square tile = 20cm x 20cm = 400 cm² ---- convert to m²

400 cm² x = 0.04 m²

To get the number of tiles required to cover the floor area 5x20 = 100 m²

just divide it by the area of tile.

so Number of tile req'd = 100 / 0.04 = 2500

therefore,

the number of tiles needed = 2500 pieces