Answer:
Area of floor = 420× 540 cm^2
Let the side of a souared tile is ACm.
then, the total area of one tiles = A×A= A^2 cm^2
now,
No of tiles × area of one tiles = area of floor.
No of tiles should be an integer, that means (420 × 540)/ A^2 should be an integer.
write the numerator in terms of its factors:-
420 = 2×2× 3× 5× 7
540 = 2× 2× 3× 3×3× 5
Multiplying both
430× 540 = 4^2 × 9^2 × 5^2 × (7^0.5)^2
Hence largest length = 4× 9×5 × 7^0.5 = 476.335 Cm.
or simply
find the sugare root of product of 420 and 540.
ans = 476.335 cm.