20 is (2/5) of a number, what is this number?
20是一个数的(2/5)，这个数是多少？
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">20 / (2/5)</gadget>
<output>50</output>

<result>50</result>