Half of a number is (4/7), what is this number
一个数的一半是(4/7)，这个数是多少
<gadget id="calculator">4 / 7</gadget>
<output>4/7 = around 0.571429</output>

<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">(4/7) / (1/2)</gadget>
<output>8/7 = around 1.142857</output>

<result>8/7 = around 1.142857</result>