How many floor tiles of 30.5cm x 30.5cm to cover 7square meters?

75.25 tiles (assuming no part of a tile is wasted and leaving no allowance for space between tiles.) buy at least 10 extra.

Math:

30.5 cm x 30.5 cm = 930.25 Square cm per tile.

a square meter = 100 cm X 100 cm = 10,000 square cm

7 square meter = 70,000 square cm

now divide.... 70,000 square cm / 930.25 square cm per tile = 75.25 tiles