Step 1 :
Divide $ 1468 $ by $ 40 $ and get the remainder

$$ 1468 : 40 = 36 \text{ ( remainder is } \color{blue}{ 28 } \text{ ) } $$

The remainder is positive ($ 28 > 0 $), so we will continue with division.

Step 2 :
Divide $ 40 $ by $ \color{blue}{ 28 } $ and get the remainder

$$ 40 : 28 = 1 \text{ ( remainder is } \color{blue}{ 12 } \text{ ) } $$

The remainder is still positive ($ 12 > 0 $), so we will continue with division.

Step 3 :
Divide $ 28 $ by $ \color{blue}{ 12 } $ and get the remainder

$$ 28 : 12 = 2 \text{ ( remainder is } \color{blue}{ 4 } \text{ ) } $$

The remainder is still positive ($ 4 > 0 $), so we will continue with division.

Step 4 :
Divide $ 12 $ by $ \color{blue}{ 4 } $ and get the remainder

$$ 12 : \color{blue}{ \boxed { 4 }} = 3 \text{ ( remainder is } \color{blue}{ 0 } \text{ ) } $$

The remainder is zero => GCD is the last divisor $ \color{blue}{ \boxed { 4 }} $.

This solution can be visualized using a Venn diagram.

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

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