Answer:
9
Explanation:
When the numbers are relatively close together, it is often useful to see if their difference is a factor:
36 -27 = 9
Checking ...
36 = 4×9
27 = 3×9
9 is the greatest common factor of 27 and 36.
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How to find the greatest common factor (GCF)
The Euclidean algorithm has you find the remainder from division of the larger by the smaller. If that remainder is zero, the smaller is the GCF. If the remainder is nonzero, it replaces the larger number and the process is repeated. When the larger number is less than twice the smaller, the remainder is their difference.