What is the greatest common factor of 51 and 119?
The factors of 51 are 1, 3, 17, and 51.
The factors of 119 are 1, 7, 17, and 119.
The factors they have in common are 1 and 17. Therefore the
greatest common factor is 17.
The greatest common factor can also be determined from the prime
factors.
The prime factors of 51 are 3 and 17.
The prime factors of 119 are 7 and 17.
The prime factors they have in common are a single 17, so the
greatest common factor is 17.