A fraction with a denominator of 28 is (2/7) after reduction. What is the fraction?
一个分数，分母是28，经过约分后是(2/7)，这个分数是多少．
<gadget id="calculator">4 / 28</gadget>
<output>1/7 = around 0.142857</output>

<gadget id="calculator">2 * (1/7)</gadget>
<output>2/7 = around 0.285714</output>

<result>2/7 = around 0.285714</result>