The GCD of given numbers is 30.
Step 1 :
Divide $ 30 $ by $ 30 $ and get the remainder
The remainder is zero => GCD is the last divisor $ \color{blue}{ \boxed { 30 }} $.
We can summarize an algorithm into a following table.
30 | : | 30 | = | 1 | remainder ( 0 ) |
GCD = 30 |
This solution can be visualized using a Venn diagram.
The GCD equals the product of the numbers at the intersection.