Answer:
The Greatest Common Factor (GCF) for 27 and 81, notation GCF(27,81), is 27.
Explanation:
The factors of 27 are 1, 3, 9,27. The common factors of 18 and 27 are 1, 3, and 9. The greatest common factor of 18 and 27 is 9.
The largest of the common factors is 27, so you can say that 27 is the greatest common factor of 27, 54, and81.
The greatest common factor of 27 and 81 is27, because 27 is the highest number that is divisible by both numbers.