3 How many consecutive subtractions (1/7) result in 0.
3连续减去多少个(1/7)结果为0．
<gadget id="calculator">1 / 7</gadget>
<output>1/7 = around 0.142857</output>

<gadget id="calculator">3 / (1/7)</gadget>
<output>21</output>

<result>21</result>