A bottle of beverage is 2 liters, father drank this bottle of beverage (5/13), mother drank this bottle of beverage (4/13), and Xiaodong drank the rest. How much of this bottle of drink did Xiaodong drink?
一瓶饮料2升，爸爸喝了这瓶饮料的(5/13)，妈妈喝了这瓶饮料的(4/13)，剩下的全由小东喝．小东喝了这瓶饮料的几分之几？
<gadget id="calculator">5 / 13</gadget>
<output>5/13 = around 0.384615</output>

<gadget id="calculator">4 / 13</gadget>
<output>4/13 = around 0.307692</output>

<gadget id="calculator">1 - (5/13) - (4/13)</gadget>
<output>4/13 = around 0.307692</output>

<result>4/13 = around 0.307692</result>