0.45 and how many are reciprocals of each other.
0.45与多少互为倒数．
<gadget id="calculator">9 / 20</gadget>
<output>9/20 = around 0.45</output>

<gadget id="calculator">1 / (9/20)</gadget>
<output>20/9 = around 2.222222</output>

<result>20/9 = around 2.222222</result>