The GCD of given numbers is 1.
| factors of 68 are : | 1 , 2 , 4 , 17 , 34 , 68 |
| factors of 9 are : | 1 , 3 , 9 |
We see that the Greatest Common Factor = 1.
This solution can be visualized using a Venn diagram.
The GCD equals the product of the numbers at the intersection.