Subtract (1/7) from 1, how many times to get 0.
从1里面减去(1/7)，减多少次后得0．
<gadget id="calculator">1 / 7</gadget>
<output>1/7 = around 0.142857</output>

<gadget id="calculator">1 / (1/7)</gadget>
<output>7</output>

<result>7</result>