Step 1 :
Divide $ 1479 $ by $ 377 $ and get the remainder

$$ 1479 : 377 = 3 \text{ ( remainder is } \color{blue}{ 348 } \text{ ) } $$

The remainder is positive ($ 348 > 0 $), so we will continue with division.

Step 2 :
Divide $ 377 $ by $ \color{blue}{ 348 } $ and get the remainder

$$ 377 : 348 = 1 \text{ ( remainder is } \color{blue}{ 29 } \text{ ) } $$

The remainder is still positive ($ 29 > 0 $), so we will continue with division.

Step 3 :
Divide $ 348 $ by $ \color{blue}{ 29 } $ and get the remainder

$$ 348 : \color{blue}{ \boxed { 29 }} = 12 \text{ ( remainder is } \color{blue}{ 0 } \text{ ) } $$

The remainder is zero => GCD is the last divisor $ \color{blue}{ \boxed { 29 }} $.

This solution can be visualized using a Venn diagram.

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

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