The GCD of given numbers is 90.
Step 1 :
Divide $ 1890 $ by $ 450 $ and get the remainder
The remainder is positive ($ 90 > 0 $), so we will continue with division.
Step 2 :
Divide $ 450 $ by $ \color{blue}{ 90 } $ and get the remainder
The remainder is zero => GCD is the last divisor $ \color{blue}{ \boxed { 90 }} $.
We can summarize an algorithm into a following table.
1890 | : | 450 | = | 4 | remainder ( 90 ) | ||
450 | : | 90 | = | 5 | remainder ( 0 ) | ||
GCD = 90 |
This solution can be visualized using a Venn diagram.
The GCD equals the product of the numbers at the intersection.