A pile of 16 tons of goods, used (3/4), how many tons left.
一堆货物16吨，用去(3/4)，还剩多少吨．
<gadget id="calculator">3 / 4</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">1 - (3/4)</gadget>
<output>1/4 = around 0.25</output>

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

<result>4</result>