When x=how much, the ratio of (1/5):x is just the smallest prime number.
当x=多少时，(1/5)：x的比值恰好是最小的质数．
<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">(1/5) / 2</gadget>
<output>1/10 = around 0.1</output>

<result>1/10 = around 0.1</result>