Step 1 :
Divide $ 590 $ by $ 167 $ and get the remainder

$$ 590 : 167 = 3 \text{ ( remainder is } \color{blue}{ 89 } \text{ ) } $$

The remainder is positive ($ 89 > 0 $), so we will continue with division.

Step 2 :
Divide $ 167 $ by $ \color{blue}{ 89 } $ and get the remainder

$$ 167 : 89 = 1 \text{ ( remainder is } \color{blue}{ 78 } \text{ ) } $$

The remainder is still positive ($ 78 > 0 $), so we will continue with division.

Step 3 :
Divide $ 89 $ by $ \color{blue}{ 78 } $ and get the remainder

$$ 89 : 78 = 1 \text{ ( remainder is } \color{blue}{ 11 } \text{ ) } $$

The remainder is still positive ($ 11 > 0 $), so we will continue with division.

Step 4 :
Divide $ 78 $ by $ \color{blue}{ 11 } $ and get the remainder

$$ 78 : 11 = 7 \text{ ( remainder is } \color{blue}{ 1 } \text{ ) } $$

The remainder is still positive ($ 1 > 0 $), so we will continue with division.

Step 5 :
Divide $ 11 $ by $ \color{blue}{ 1 } $ and get the remainder

$$ 11 : \color{blue}{ \boxed { 1 }} = 11 \text{ ( remainder is } \color{blue}{ 0 } \text{ ) } $$

The remainder is zero => GCD is the last divisor $ \color{blue}{ \boxed { 1 }} $.

This solution can be visualized using a Venn diagram.

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

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