There are 100 cm in 1 meter. The dimensions are 400cm by 250cm. Depending on which way you turn them, they will fit better.
If you take 400 divided by 16, you will have a row of 25 wide and if you divide 250 by 10, you will have a length of 25.
You now have 25 rows of 25. 25x25 is 625 tiles.
