The GCD of given numbers is 15.
Step 1 : Place the numbers inside division bar:.
| 105 | 135 |
Step 2 : Divide numbers by 3.
| 3 | 105 | 135 |
| 35 | 45 |
Step 3 : Divide numbers by 5.
| 3 | 105 | 135 |
| 5 | 35 | 45 |
| 7 | 9 |
Step 4 : Number 7 and 9, cannot be divided any more. The GCD is:
$$ GCD = 3\cdot5 = 15 $$This solution can be visualized using a Venn diagram.
The GCD equals the product of the numbers at the intersection.