A room measures 540cm by 420cm find the length of the largest square tiles that can be used to cover the floor with out requiring any cutting ?

Answer 1

540 = 2^2 3^3 5^1
420 = 2^2 3^1 5^1 7^1
2^2 = 4 is the only common square factor, so use
135 by 105 tiles, each 2x2

Answer 2

What is the answer left in powers