The sum of the ages of the father and the daughter is 91. When the father's age is twice the daughter's current age, the daughter's age is (1/3) the father's current age. Find the daughter's current age.
父亲和女儿的年龄之和是91，当父亲的年龄是女儿现在年龄的2倍的时候，女儿的年龄是父亲现在在年龄的(1/3)，求女儿现在的年龄．
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">(1/3) * 91</gadget>
<output>91/3 = around 30.333333</output>

<gadget id="calculator">91 + (91/3)</gadget>
<output>364/3 = around 121.333333</output>

<gadget id="calculator">1 + 1 + 2 + (1/3)</gadget>
<output>13/3 = around 4.333333</output>

<gadget id="calculator">(364/3) / (13/3)</gadget>
<output>28</output>

<result>28</result>