What is the greatest common factor of 77, 66 and 88?

To find the greatest common factor (GCF) of 77, 66, and 88, follow these steps:

1. First, find the prime factors of each number.

   • The prime factors of 77 are 7 and 11.
   • The prime factors of 66 are 2, 3, and 11.
   • The prime factors of 88 are 2, 2, 2, and 11.

2. Next, identify the common prime factors.

   • The common prime factor for all three numbers is 11.

3. The greatest common factor is the highest number that divides exactly into each of the numbers. In this case, the GCF is 11.