Question 1167614
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The ratio of the numbers of square tiles of the two sizes required to cover the floor is 480:270 = 16:9.<br>
That means the ratio of the areas of the two sizes of square tiles is 9:16; and that means the ratio of the side lengths of the two sizes of tiles is 3:4.<br>
So let the two side lengths be 3x and 4x.  Then knowing that the side length of the larger tile is 3 inches more than the side length of the smaller,<br>
{{{4x-3x=3}}}
{{{x=3}}}<br>
ANSWER: The side length of the tiles on the floor is 3x=9 inches.<br>