Because 2.9*0.4=1.16, so 1.16/2.9=how much.
因为2.9*0.4=1.16，所以1.16/2.9=多少．
<gadget id="calculator">0.4 / 2.9</gadget>
<output>0.137931</output>

<gadget id="calculator">2.9 * 0.137931</gadget>
<output>0.4</output>

<result>0.4</result>