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$$\frac { 7 }{ 20 } +\frac { 3 }{ 10 } = $$

$\cfrac { 10 }{ 30 }$

$\cfrac { 1 }{ 3 }$

$\cfrac { 13 }{ 20 }$

$\cfrac { 1 }{ 2 }$

$\cfrac { 4 }{ 10 }$