Step 1 :
Divide $ 183 $ by $ 37 $ and get the remainder

$$ 183 : 37 = 4 \text{ ( remainder is } \color{blue}{ 35 } \text{ ) } $$

The remainder is positive ($ 35 > 0 $), so we will continue with division.

Step 2 :
Divide $ 37 $ by $ \color{blue}{ 35 } $ and get the remainder

$$ 37 : 35 = 1 \text{ ( remainder is } \color{blue}{ 2 } \text{ ) } $$

The remainder is still positive ($ 2 > 0 $), so we will continue with division.

Step 3 :
Divide $ 35 $ by $ \color{blue}{ 2 } $ and get the remainder

$$ 35 : 2 = 17 \text{ ( remainder is } \color{blue}{ 1 } \text{ ) } $$

The remainder is still positive ($ 1 > 0 $), so we will continue with division.

Step 4 :
Divide $ 2 $ by $ \color{blue}{ 1 } $ and get the remainder

$$ 2 : \color{blue}{ \boxed { 1 }} = 2 \text{ ( remainder is } \color{blue}{ 0 } \text{ ) } $$

The remainder is zero => GCD is the last divisor $ \color{blue}{ \boxed { 1 }} $.

This solution can be visualized using a Venn diagram.

The GCD equals the product of the numbers at the intersection.

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