What is the GCF of 72 and 81?
Greatest Common Factor of 72 and 81 is the largest possible number which divides both 72 and 81 exactly.
Answer: GCF of 72 and 81 is 9
Lets see how to find the GCF of 72 and 81
Explanation:
GCF of 72 and 81 by Listing the Common Factors
Factors of 72: 1, 2, 3, 4, 6, 8, 9, 12, 18, 24, 36, 72
Factors of 81 : 1, 3, 9, 27, 81
Common Factors of 72 and 81: 1, 3, 9
Since the greatest common factor of 72 and 81 is 9, we say GCF of 72 and 81 is 9
GCF of 72 and 81 by Long Division

Step 1: Divide the largest number 81 by the smaller number 72 and check the remainder. Here, the remainder is 9.

Step 2: Make the remainder 9 as the divisor and the divisor 72 as the dividend and perform the long division again.

Step 3: Continue till you get the remainder as 0 and GCF of 72 and 81 is the last divisor obtained.
You can find the GCF of 72 and 81 in any of the above methods but the solution will be the same.