Step 1 :
Divide $ 288 $ by $ 56 $ and get the remainder

$$ 288 : 56 = 5 \text{ ( remainder is } \color{blue}{ 8 } \text{ ) } $$

The remainder is positive ($ 8 > 0 $), so we will continue with division.

Step 2 :
Divide $ 56 $ by $ \color{blue}{ 8 } $ and get the remainder

$$ 56 : \color{blue}{ \boxed { 8 }} = 7 \text{ ( remainder is } \color{blue}{ 0 } \text{ ) } $$

The remainder is zero => GCD is the last divisor $ \color{blue}{ \boxed { 8 }} $.

This solution can be visualized using a Venn diagram.

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

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