Step 1 :
Divide $ 4900 $ by $ 602 $ and get the remainder

$$ 4900 : 602 = 8 \text{ ( remainder is } \color{blue}{ 84 } \text{ ) } $$

The remainder is positive ($ 84 > 0 $), so we will continue with division.

Step 2 :
Divide $ 602 $ by $ \color{blue}{ 84 } $ and get the remainder

$$ 602 : 84 = 7 \text{ ( remainder is } \color{blue}{ 14 } \text{ ) } $$

The remainder is still positive ($ 14 > 0 $), so we will continue with division.

Step 3 :
Divide $ 84 $ by $ \color{blue}{ 14 } $ and get the remainder

$$ 84 : \color{blue}{ \boxed { 14 }} = 6 \text{ ( remainder is } \color{blue}{ 0 } \text{ ) } $$

The remainder is zero => GCD is the last divisor $ \color{blue}{ \boxed { 14 }} $.

This solution can be visualized using a Venn diagram.

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

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