(2/7) plus how much is equal to the smallest prime number.
(2/7)加上多少就等于最小的质数．
<gadget id="calculator">2 / 7</gadget>
<output>2/7 = around 0.285714</output>

<gadget id="calculator">2 - (2/7)</gadget>
<output>12/7 = around 1.714286</output>

<result>12/7 = around 1.714286</result>