Step 1 :
Divide $ 6600 $ by $ 5544 $ and get the remainder

$$ 6600 : 5544 = 1 \text{ ( remainder is } \color{blue}{ 1056 } \text{ ) } $$

The remainder is positive ($ 1056 > 0 $), so we will continue with division.

Step 2 :
Divide $ 5544 $ by $ \color{blue}{ 1056 } $ and get the remainder

$$ 5544 : 1056 = 5 \text{ ( remainder is } \color{blue}{ 264 } \text{ ) } $$

The remainder is still positive ($ 264 > 0 $), so we will continue with division.

Step 3 :
Divide $ 1056 $ by $ \color{blue}{ 264 } $ and get the remainder

$$ 1056 : \color{blue}{ \boxed { 264 }} = 4 \text{ ( remainder is } \color{blue}{ 0 } \text{ ) } $$

The remainder is zero => GCD is the last divisor $ \color{blue}{ \boxed { 264 }} $.

This solution can be visualized using a Venn diagram.

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

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