Subtract (1/4) from 4 each time, how many times to get 0.
从4里面每次减去(1/4)，减多少次得0．
<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">4 / (1/4)</gadget>
<output>16</output>

<result>16</result>