Answer:
48 inches
Explanation:
The greatest common factor of 144 and 240 is 48. If Hector orders 48" square tiles, he can use 3 of them in the direction of the short dimension, and 5 of them in the direction of the long dimension.
The tiles can be 48 inches square.
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Using Euclid's algorithm to find the GCF, we have ...
240/144 = 1 r 96
144/96 = 1 r 48
96/48 = 2 r 0 . . . . . 48 is the GCF
At each step, if the remainder from the division is not zero, we replace the larger number with the remainder and do the division again. The divisor that gives a zero remainder is the GCF.